--- a/gfx/layers/wr/WebRenderDisplayItemLayer.cpp
+++ b/gfx/layers/wr/WebRenderDisplayItemLayer.cpp
@@ -110,16 +110,17 @@ WebRenderDisplayItemLayer::SendImageCont
     mImageContainer = aContainer;
   }
 
   return mKey;
 }
 
 bool
 WebRenderDisplayItemLayer::PushItemAsImage(wr::DisplayListBuilder& aBuilder,
+                                           const StackingContextHelper& aSc,
                                            nsTArray<layers::WebRenderParentCommand>& aParentCommands)
 {
   if (!mImageContainer) {
     mImageContainer = LayerManager::CreateImageContainer();
   }
 
   if (!mImageClient) {
     mImageClient = ImageClient::CreateImageClient(CompositableType::IMAGE,

--- a/gfx/layers/wr/WebRenderDisplayItemLayer.h
+++ b/gfx/layers/wr/WebRenderDisplayItemLayer.h
@@ -24,16 +24,17 @@ public:
     : DisplayItemLayer(aLayerManager, static_cast<WebRenderLayer*>(this))
   {
     MOZ_COUNT_CTOR(WebRenderDisplayItemLayer);
   }
 
   Maybe<wr::ImageKey> SendImageContainer(ImageContainer* aContainer,
                                          nsTArray<layers::WebRenderParentCommand>& aParentCommands);
   bool PushItemAsImage(wr::DisplayListBuilder& aBuilder,
+                       const StackingContextHelper& aSc,
                        nsTArray<layers::WebRenderParentCommand>& aParentCommands);
 
 protected:
   virtual ~WebRenderDisplayItemLayer();
 
 public:
   Layer* GetLayer() override { return this; }
   void RenderLayer(wr::DisplayListBuilder& aBuilder,

--- a/layout/forms/nsButtonFrameRenderer.cpp
+++ b/layout/forms/nsButtonFrameRenderer.cpp
@@ -211,20 +211,21 @@ nsDisplayButtonBorder::CreateWebRenderCo
                                                nsTArray<WebRenderParentCommand>& aCommands,
                                                WebRenderDisplayItemLayer* aLayer)
 {
   MOZ_ASSERT(mBorderRenderer);
   // This is really a combination of paint box shadow inner +
   // paint border.
   nsRect buttonRect = nsRect(ToReferenceFrame(), mFrame->GetSize());
   nsDisplayBoxShadowInner::CreateInsetBoxShadowWebRenderCommands(aBuilder,
+                                                                 aSc,
                                                                  aLayer,
                                                                  mFrame,
                                                                  buttonRect);
-  mBorderRenderer->CreateWebRenderCommands(aBuilder, aLayer);
+  mBorderRenderer->CreateWebRenderCommands(aBuilder, aSc, aLayer);
 }
 
 void
 nsDisplayButtonBorder::ComputeInvalidationRegion(
   nsDisplayListBuilder* aBuilder,
   const nsDisplayItemGeometry* aGeometry,
   nsRegion *aInvalidRegion)
 {
@@ -374,17 +375,17 @@ nsDisplayButtonForeground::BuildLayer(ns
 
 void
 nsDisplayButtonForeground::CreateWebRenderCommands(wr::DisplayListBuilder& aBuilder,
                                                    const StackingContextHelper& aSc,
                                                    nsTArray<WebRenderParentCommand>& aParentCommands,
                                                    mozilla::layers::WebRenderDisplayItemLayer* aLayer)
 {
   MOZ_ASSERT(mBorderRenderer.isSome());
-  mBorderRenderer->CreateWebRenderCommands(aBuilder, aLayer);
+  mBorderRenderer->CreateWebRenderCommands(aBuilder, aSc, aLayer);
 }
 
 nsresult
 nsButtonFrameRenderer::DisplayButton(nsDisplayListBuilder* aBuilder,
                                      nsDisplayList* aBackground,
                                      nsDisplayList* aForeground)
 {
   if (mFrame->StyleEffects()->mBoxShadow) {

--- a/layout/generic/nsBulletFrame.cpp
+++ b/layout/generic/nsBulletFrame.cpp
@@ -487,17 +487,17 @@ BulletRenderer::CreateWebRenderCommandsF
                                                wr::DisplayListBuilder& aBuilder,
                                                const layers::StackingContextHelper& aSc,
                                                nsTArray<layers::WebRenderParentCommand>& aParentCommands,
                                                layers::WebRenderDisplayItemLayer* aLayer)
 {
   MOZ_ASSERT(IsPathType());
   MOZ_ASSERT(aLayer->GetDisplayItem() == aItem);
 
-  if (!aLayer->PushItemAsImage(aBuilder, aParentCommands)) {
+  if (!aLayer->PushItemAsImage(aBuilder, aSc, aParentCommands)) {
     NS_WARNING("Fail to create WebRender commands for Bullet path.");
   }
 }
 
 void
 BulletRenderer::CreateWebRenderCommandsForText(nsDisplayItem* aItem,
                                                wr::DisplayListBuilder& aBuilder,
                                                const layers::StackingContextHelper& aSc,

--- a/layout/generic/nsColumnSetFrame.cpp
+++ b/layout/generic/nsColumnSetFrame.cpp
@@ -103,17 +103,17 @@ nsDisplayColumnRule::BuildLayer(nsDispla
 void
 nsDisplayColumnRule::CreateWebRenderCommands(wr::DisplayListBuilder& aBuilder,
                                              const StackingContextHelper& aSc,
                                              nsTArray<WebRenderParentCommand>& aParentCommands,
                                              WebRenderDisplayItemLayer* aLayer)
 {
   MOZ_ASSERT(!mBorderRenderers.IsEmpty());
   for (auto iter = mBorderRenderers.begin(); iter != mBorderRenderers.end(); iter++) {
-      iter->CreateWebRenderCommands(aBuilder, aLayer);
+      iter->CreateWebRenderCommands(aBuilder, aSc, aLayer);
   }
 }
 
 /**
  * Tracking issues:
  *
  * XXX cursor movement around the top and bottom of colums seems to make the editor
  * lose the caret.

--- a/layout/painting/nsCSSRendering.cpp
+++ b/layout/painting/nsCSSRendering.cpp
@@ -1970,16 +1970,17 @@ nsCSSRendering::CanBuildWebRenderDisplay
   // We only support painting gradients and image for a single style image layer
   return aBackgroundStyle->mImage.mLayers[aLayer].mImage.GetType() == eStyleImageType_Gradient ||
          aBackgroundStyle->mImage.mLayers[aLayer].mImage.GetType() == eStyleImageType_Image;
 }
 
 DrawResult
 nsCSSRendering::BuildWebRenderDisplayItemsForStyleImageLayer(const PaintBGParams& aParams,
                                                              mozilla::wr::DisplayListBuilder& aBuilder,
+                                                             const mozilla::layers::StackingContextHelper& aSc,
                                                              nsTArray<WebRenderParentCommand>& aParentCommands,
                                                              mozilla::layers::WebRenderDisplayItemLayer* aLayer)
 {
   NS_PRECONDITION(aParams.frame,
                   "Frame is expected to be provided to BuildWebRenderDisplayItemsForStyleImageLayer");
 
   nsStyleContext *sc;
   if (!FindBackground(aParams.frame, &sc)) {
@@ -1995,17 +1996,17 @@ nsCSSRendering::BuildWebRenderDisplayIte
     nsIContent* content = aParams.frame->GetContent();
     if (!content || content->GetParent()) {
       return DrawResult::NOT_READY;
     }
 
     sc = aParams.frame->StyleContext();
   }
 
-  return BuildWebRenderDisplayItemsForStyleImageLayerWithSC(aParams, aBuilder, aParentCommands, aLayer,
+  return BuildWebRenderDisplayItemsForStyleImageLayerWithSC(aParams, aBuilder, aSc, aParentCommands, aLayer,
                                                             sc, *aParams.frame->StyleBorder());
 }
 
 static bool
 IsOpaqueBorderEdge(const nsStyleBorder& aBorder, mozilla::Side aSide)
 {
   if (aBorder.GetComputedBorder().Side(aSide) == 0)
     return true;
@@ -2711,16 +2712,17 @@ nsCSSRendering::PaintStyleImageLayerWith
   }
 
   return result;
 }
 
 DrawResult
 nsCSSRendering::BuildWebRenderDisplayItemsForStyleImageLayerWithSC(const PaintBGParams& aParams,
                                                                    mozilla::wr::DisplayListBuilder& aBuilder,
+                                                                   const mozilla::layers::StackingContextHelper& aSc,
                                                                    nsTArray<WebRenderParentCommand>& aParentCommands,
                                                                    mozilla::layers::WebRenderDisplayItemLayer* aLayer,
                                                                    nsStyleContext *aBackgroundSC,
                                                                    const nsStyleBorder& aBorder)
 {
   MOZ_ASSERT(CanBuildWebRenderDisplayItemsForStyleImageLayer(aParams.presCtx,
                                                              aParams.frame,
                                                              aBackgroundSC->StyleBackground(),
@@ -2756,17 +2758,17 @@ nsCSSRendering::BuildWebRenderDisplayIte
 
   nsBackgroundLayerState state =
     PrepareImageLayer(&aParams.presCtx, aParams.frame,
                       aParams.paintFlags, paintBorderArea,
                       clipState.mBGClipArea, layer, nullptr);
 
   if (!state.mFillArea.IsEmpty()) {
     return state.mImageRenderer.BuildWebRenderDisplayItemsForLayer(&aParams.presCtx,
-                                     aBuilder, aParentCommands, aLayer,
+                                     aBuilder, aSc, aParentCommands, aLayer,
                                      state.mDestArea, state.mFillArea,
                                      state.mAnchor + paintBorderArea.TopLeft(),
                                      clipState.mDirtyRectInAppUnits,
                                      state.mRepeatSize, aParams.opacity);
   }
 
   return DrawResult::SUCCESS;
 }

--- a/layout/painting/nsCSSRendering.h
+++ b/layout/painting/nsCSSRendering.h
@@ -28,16 +28,17 @@ namespace mozilla {
 
 namespace gfx {
 struct Color;
 class DrawTarget;
 } // namespace gfx
 
 namespace layers {
 class ImageContainer;
+class StackingContextHelper;
 class WebRenderDisplayItemLayer;
 class WebRenderParentCommand;
 } // namespace layers
 
 namespace wr {
 class DisplayListBuilder;
 } // namespace wr
 
@@ -492,21 +493,23 @@ struct nsCSSRendering {
                                                const nsStyleBorder& aBorder);
 
   static bool CanBuildWebRenderDisplayItemsForStyleImageLayer(nsPresContext& aPresCtx,
                                                               nsIFrame *aFrame,
                                                               const nsStyleBackground* aBackgroundStyle,
                                                               int32_t aLayer);
   static DrawResult BuildWebRenderDisplayItemsForStyleImageLayer(const PaintBGParams& aParams,
                                                                  mozilla::wr::DisplayListBuilder& aBuilder,
+                                                                 const mozilla::layers::StackingContextHelper& aSc,
                                                                  nsTArray<mozilla::layers::WebRenderParentCommand>& aParentCommands,
                                                                  mozilla::layers::WebRenderDisplayItemLayer* aLayer);
 
   static DrawResult BuildWebRenderDisplayItemsForStyleImageLayerWithSC(const PaintBGParams& aParams,
                                                                        mozilla::wr::DisplayListBuilder& aBuilder,
+                                                                       const mozilla::layers::StackingContextHelper& aSc,
                                                                        nsTArray<mozilla::layers::WebRenderParentCommand>& aParentCommands,
                                                                        mozilla::layers::WebRenderDisplayItemLayer* aLayer,
                                                                        nsStyleContext *mBackgroundSC,
                                                                        const nsStyleBorder& aBorder);
 
   /**
    * Returns the rectangle covered by the given background layer image, taking
    * into account background positioning, sizing, and repetition, but not

--- a/layout/painting/nsCSSRenderingBorders.cpp
+++ b/layout/painting/nsCSSRenderingBorders.cpp
@@ -3546,16 +3546,17 @@ nsCSSBorderRenderer::CanCreateWebRenderC
     }
   }
 
   return true;
 }
 
 void
 nsCSSBorderRenderer::CreateWebRenderCommands(wr::DisplayListBuilder& aBuilder,
+                                             const layers::StackingContextHelper& aSc,
                                              layers::WebRenderDisplayItemLayer* aLayer,
                                              gfx::Rect aClipRect)
 {
   LayoutDeviceRect outerRect = LayoutDeviceRect::FromUnknownRect(mOuterRect);
   LayerRect transformedRect = aLayer->RelativeToParent(outerRect);
   WrBorderSide side[4];
   NS_FOR_CSS_SIDES(i) {
     side[i] = wr::ToWrBorderSide(ToDeviceColor(mBorderColors[i]), mBorderStyles[i]);

--- a/layout/painting/nsCSSRenderingBorders.h
+++ b/layout/painting/nsCSSRenderingBorders.h
@@ -25,16 +25,17 @@
 struct nsBorderColors;
 class nsDisplayBorder;
 
 namespace mozilla {
 namespace gfx {
 class GradientStops;
 } // namespace gfx
 namespace layers {
+class StackingContextHelper;
 class WebRenderDisplayItemLayer;
 } // namespace layers
 } // namespace mozilla
 
 // define this to enable a bunch of debug dump info
 #undef DEBUG_NEW_BORDERS
 
 /*
@@ -102,16 +103,17 @@ public:
                       nsBorderColors* const* aCompositeColors,
                       nscolor aBackgroundColor);
 
   // draw the entire border
   void DrawBorders();
 
   bool CanCreateWebRenderCommands();
   void CreateWebRenderCommands(mozilla::wr::DisplayListBuilder& aBuilder,
+                               const mozilla::layers::StackingContextHelper& aSc,
                                mozilla::layers::WebRenderDisplayItemLayer* aLayer,
                                Rect aClipRect = Rect(0, 0, 0, 0));
 
   // utility function used for background painting as well as borders
   static void ComputeInnerRadii(const RectCornerRadii& aRadii,
                                 const Float* aBorderSizes,
                                 RectCornerRadii* aInnerRadiiRet);
 

--- a/layout/painting/nsCSSRenderingGradients.cpp
+++ b/layout/painting/nsCSSRenderingGradients.cpp
@@ -1022,16 +1022,17 @@ nsCSSGradientRenderer::BuildWebRenderPar
 
   aLineStart = LayoutDevicePoint(mLineStart.x, mLineStart.y);
   aLineEnd = LayoutDevicePoint(mLineEnd.x, mLineEnd.y);
   aGradientRadius = LayoutDeviceSize(mRadiusX, mRadiusY);
 }
 
 void
 nsCSSGradientRenderer::BuildWebRenderDisplayItems(wr::DisplayListBuilder& aBuilder,
+                                                  const layers::StackingContextHelper& aSc,
                                                   layers::WebRenderDisplayItemLayer* aLayer,
                                                   const nsRect& aDest,
                                                   const nsRect& aFillArea,
                                                   const nsSize& aRepeatSize,
                                                   const CSSIntRect& aSrc,
                                                   float aOpacity)
 {
   if (aDest.IsEmpty() || aFillArea.IsEmpty()) {

--- a/layout/painting/nsCSSRenderingGradients.h
+++ b/layout/painting/nsCSSRenderingGradients.h
@@ -10,16 +10,17 @@
 #include "nsStyleStruct.h"
 #include "Units.h"
 #include "mozilla/Maybe.h"
 #include "mozilla/gfx/2D.h"
 
 namespace mozilla {
 
 namespace layers {
+class StackingContextHelper;
 class WebRenderDisplayItemLayer;
 } // namespace layers
 
 namespace wr {
 class DisplayListBuilder;
 } // namespace wr
 
 // A resolved color stop, with a specific position along the gradient line and
@@ -75,16 +76,17 @@ public:
    * aLayer - the layer to make this display item relative to
    * aDest - where the first tile of gradient is
    * aFill - the area to be filled with tiles of aDest
    * aRepeatSize - the distance from the origin of a tile
    *               to the next origin of a tile
    * aSrc - the area of the gradient that will fill aDest
    */
   void BuildWebRenderDisplayItems(wr::DisplayListBuilder& aBuilder,
+                                  const layers::StackingContextHelper& aSc,
                                   layers::WebRenderDisplayItemLayer* aLayer,
                                   const nsRect& aDest,
                                   const nsRect& aFill,
                                   const nsSize& aRepeatSize,
                                   const mozilla::CSSIntRect& aSrc,
                                   float aOpacity = 1.0);
 
 private:

--- a/layout/painting/nsDisplayList.cpp
+++ b/layout/painting/nsDisplayList.cpp
@@ -3437,17 +3437,17 @@ nsDisplayBackgroundImage::CreateWebRende
   nsCSSRendering::PaintBGParams params =
     nsCSSRendering::PaintBGParams::ForSingleLayer(*mFrame->PresContext(),
                                                   mVisibleRect, mBackgroundRect,
                                                   mFrame, 0, mLayer,
                                                   CompositionOp::OP_OVER);
   params.bgClipRect = &mBounds;
 
   image::DrawResult result =
-    nsCSSRendering::BuildWebRenderDisplayItemsForStyleImageLayer(params, aBuilder, aParentCommands, aLayer);
+    nsCSSRendering::BuildWebRenderDisplayItemsForStyleImageLayer(params, aBuilder, aSc, aParentCommands, aLayer);
 
   nsDisplayBackgroundGeometry::UpdateDrawResult(this, result);
 }
 
 void
 nsDisplayBackgroundImage::HitTest(nsDisplayListBuilder* aBuilder,
                                   const nsRect& aRect,
                                   HitTestState* aState,
@@ -4234,17 +4234,17 @@ nsDisplayOutline::CreateWebRenderCommand
   MOZ_ASSERT(mBorderRenderer.isSome());
 
   gfx::Rect clip(0, 0, 0, 0);
   if (GetClip().HasClip()) {
     int32_t appUnitsPerDevPixel = mFrame->PresContext()->AppUnitsPerDevPixel();
     clip = LayoutDeviceRect::FromAppUnits(
         GetClip().GetClipRect(), appUnitsPerDevPixel).ToUnknownRect();
   }
-  mBorderRenderer->CreateWebRenderCommands(aBuilder, aLayer, clip);
+  mBorderRenderer->CreateWebRenderCommands(aBuilder, aSc, aLayer, clip);
 }
 
 bool
 nsDisplayOutline::IsInvisibleInRect(const nsRect& aRect)
 {
   const nsStyleOutline* outline = mFrame->StyleOutline();
   nsRect borderBox(ToReferenceFrame(), mFrame->GetSize());
   if (borderBox.Contains(aRect) &&
@@ -4753,16 +4753,17 @@ nsDisplayBorder::BuildLayer(nsDisplayLis
     layer->SetBaseTransform(gfx::Matrix4x4::Translation(aContainerParameters.mOffset.x,
                                                         aContainerParameters.mOffset.y, 0));
     return layer.forget();
   }
 }
 
 void
 nsDisplayBorder::CreateBorderImageWebRenderCommands(mozilla::wr::DisplayListBuilder& aBuilder,
+                                                    const StackingContextHelper& aSc,
                                                     nsTArray<WebRenderParentCommand>& aParentCommands,
                                                     WebRenderDisplayItemLayer* aLayer)
 {
   MOZ_ASSERT(mBorderImageRenderer);
   if (!mBorderImageRenderer->mImageRenderer.IsReady()) {
     return;
   }
 
@@ -4870,26 +4871,26 @@ void
 nsDisplayBorder::CreateWebRenderCommands(wr::DisplayListBuilder& aBuilder,
                                          const StackingContextHelper& aSc,
                                          nsTArray<WebRenderParentCommand>& aParentCommands,
                                          WebRenderDisplayItemLayer* aLayer)
 {
   MOZ_ASSERT(mBorderImageRenderer || mBorderRenderer);
 
   if (mBorderImageRenderer) {
-    CreateBorderImageWebRenderCommands(aBuilder, aParentCommands, aLayer);
+    CreateBorderImageWebRenderCommands(aBuilder, aSc, aParentCommands, aLayer);
   } else if (mBorderRenderer) {
     gfx::Rect clip(0, 0, 0, 0);
     if (GetClip().HasClip()) {
       int32_t appUnitsPerDevPixel = mFrame->PresContext()->AppUnitsPerDevPixel();
       clip = LayoutDeviceRect::FromAppUnits(
           GetClip().GetClipRect(), appUnitsPerDevPixel).ToUnknownRect();
     }
 
-    mBorderRenderer->CreateWebRenderCommands(aBuilder, aLayer, clip);
+    mBorderRenderer->CreateWebRenderCommands(aBuilder, aSc, aLayer, clip);
   }
 }
 
 void
 nsDisplayBorder::Paint(nsDisplayListBuilder* aBuilder,
                        nsRenderingContext* aCtx) {
   nsPoint offset = ToReferenceFrame();
 
@@ -5334,16 +5335,17 @@ nsDisplayBoxShadowInner::BuildLayer(nsDi
                                     LayerManager* aManager,
                                     const ContainerLayerParameters& aContainerParameters)
 {
   return BuildDisplayItemLayer(aBuilder, aManager, aContainerParameters);
 }
 
 /* static */ void
 nsDisplayBoxShadowInner::CreateInsetBoxShadowWebRenderCommands(mozilla::wr::DisplayListBuilder& aBuilder,
+                                                               const StackingContextHelper& aSc,
                                                                WebRenderDisplayItemLayer* aLayer,
                                                                nsIFrame* aFrame,
                                                                const nsRect aBorderRect)
 {
   if (!nsCSSRendering::ShouldPaintBoxShadowInner(aFrame)) {
     return;
   }
 
@@ -5404,17 +5406,17 @@ void
 nsDisplayBoxShadowInner::CreateWebRenderCommands(mozilla::wr::DisplayListBuilder& aBuilder,
                                                  const StackingContextHelper& aSc,
                                                  nsTArray<WebRenderParentCommand>& aCommands,
                                                  WebRenderDisplayItemLayer* aLayer)
 {
   nsPoint offset = ToReferenceFrame();
   nsRect borderRect = nsRect(offset, mFrame->GetSize());
 
-  nsDisplayBoxShadowInner::CreateInsetBoxShadowWebRenderCommands(aBuilder, aLayer, mFrame, borderRect);
+  nsDisplayBoxShadowInner::CreateInsetBoxShadowWebRenderCommands(aBuilder, aSc, aLayer, mFrame, borderRect);
 }
 
 bool
 nsDisplayBoxShadowInner::ComputeVisibility(nsDisplayListBuilder* aBuilder,
                                            nsRegion* aVisibleRegion) {
   if (!nsDisplayItem::ComputeVisibility(aBuilder, aVisibleRegion)) {
     return false;
   }

--- a/layout/painting/nsDisplayList.h
+++ b/layout/painting/nsDisplayList.h
@@ -2861,16 +2861,17 @@ public:
   virtual nsRegion GetTightBounds(nsDisplayListBuilder* aBuilder, bool* aSnap) override
   {
     *aSnap = true;
     return CalculateBounds(*mFrame->StyleBorder());
   }
 
 protected:
   void CreateBorderImageWebRenderCommands(mozilla::wr::DisplayListBuilder& aBuilder,
+                                          const StackingContextHelper& aSc,
                                           nsTArray<WebRenderParentCommand>& aParentCommands,
                                           WebRenderDisplayItemLayer* aLayer);
   nsRegion CalculateBounds(const nsStyleBorder& aStyleBorder);
 
   mozilla::Array<mozilla::gfx::Color, 4> mColors;
   mozilla::Array<mozilla::LayerCoord, 4> mWidths;
   mozilla::Array<mozilla::LayerSize, 4> mCorners;
   mozilla::Array<uint8_t, 4> mBorderStyles;
@@ -3452,16 +3453,17 @@ public:
       aInvalidRegion->Or(geometry->mBounds, GetBounds(aBuilder, &snap));
     }
   }
 
   static bool CanCreateWebRenderCommands(nsDisplayListBuilder* aBuilder,
                                          nsIFrame* aFrame,
                                          nsPoint aReferencePoint);
   static void CreateInsetBoxShadowWebRenderCommands(mozilla::wr::DisplayListBuilder& aBuilder,
+                                                    const StackingContextHelper& aSc,
                                                     WebRenderDisplayItemLayer* aLayer,
                                                     nsIFrame* aFrame,
                                                     const nsRect aBorderRect);
   virtual LayerState GetLayerState(nsDisplayListBuilder* aBuilder,
                                    LayerManager* aManager,
                                    const ContainerLayerParameters& aParameters) override;
   virtual already_AddRefed<Layer> BuildLayer(nsDisplayListBuilder* aBuilder,
                                              LayerManager* aManager,

--- a/layout/painting/nsImageRenderer.cpp
+++ b/layout/painting/nsImageRenderer.cpp
@@ -574,16 +574,17 @@ nsImageRenderer::Draw(nsPresContext*    
   }
 
   return result;
 }
 
 DrawResult
 nsImageRenderer::BuildWebRenderDisplayItems(nsPresContext*       aPresContext,
                                             mozilla::wr::DisplayListBuilder&            aBuilder,
+                                            const mozilla::layers::StackingContextHelper& aSc,
                                             nsTArray<WebRenderParentCommand>&           aParentCommands,
                                             mozilla::layers::WebRenderDisplayItemLayer* aLayer,
                                             const nsRect&        aDirtyRect,
                                             const nsRect&        aDest,
                                             const nsRect&        aFill,
                                             const nsPoint&       aAnchor,
                                             const nsSize&        aRepeatSize,
                                             const CSSIntRect&    aSrc,
@@ -599,17 +600,17 @@ nsImageRenderer::BuildWebRenderDisplayIt
   }
 
   switch (mType) {
     case eStyleImageType_Gradient:
     {
       nsCSSGradientRenderer renderer =
         nsCSSGradientRenderer::Create(aPresContext, mGradientData, mSize);
 
-      renderer.BuildWebRenderDisplayItems(aBuilder, aLayer, aDest, aFill, aRepeatSize, aSrc, aOpacity);
+      renderer.BuildWebRenderDisplayItems(aBuilder, aSc, aLayer, aDest, aFill, aRepeatSize, aSrc, aOpacity);
       break;
     }
     case eStyleImageType_Image:
     {
       RefPtr<layers::ImageContainer> container = mImageContainer->GetImageContainer(aLayer->WrManager(),
                                                                                     ConvertImageRendererToDrawFlags(mFlags));
       if (!container) {
         NS_WARNING("Failed to get image container");
@@ -708,16 +709,17 @@ nsImageRenderer::DrawLayer(nsPresContext
                          nsPresContext::AppUnitsToIntCSSPixels(mSize.width),
                          nsPresContext::AppUnitsToIntCSSPixels(mSize.height)),
               aOpacity);
 }
 
 DrawResult
 nsImageRenderer::BuildWebRenderDisplayItemsForLayer(nsPresContext*       aPresContext,
                                                     mozilla::wr::DisplayListBuilder& aBuilder,
+                                                    const mozilla::layers::StackingContextHelper& aSc,
                                                     nsTArray<WebRenderParentCommand>& aParentCommands,
                                                     WebRenderDisplayItemLayer*       aLayer,
                                                     const nsRect&        aDest,
                                                     const nsRect&        aFill,
                                                     const nsPoint&       aAnchor,
                                                     const nsRect&        aDirty,
                                                     const nsSize&        aRepeatSize,
                                                     float                aOpacity)
@@ -726,17 +728,17 @@ nsImageRenderer::BuildWebRenderDisplayIt
     NS_NOTREACHED("Ensure PrepareImage() has returned true before calling me");
     return mPrepareResult;
   }
   if (aDest.IsEmpty() || aFill.IsEmpty() ||
       mSize.width <= 0 || mSize.height <= 0) {
     return DrawResult::SUCCESS;
   }
 
-  return BuildWebRenderDisplayItems(aPresContext, aBuilder, aParentCommands, aLayer,
+  return BuildWebRenderDisplayItems(aPresContext, aBuilder, aSc, aParentCommands, aLayer,
                                     aDirty, aDest, aFill, aAnchor, aRepeatSize,
                                     CSSIntRect(0, 0,
                                                nsPresContext::AppUnitsToIntCSSPixels(mSize.width),
                                                nsPresContext::AppUnitsToIntCSSPixels(mSize.height)),
                                     aOpacity);
 }
 
 /**

--- a/layout/painting/nsImageRenderer.h
+++ b/layout/painting/nsImageRenderer.h
@@ -9,16 +9,17 @@
 #include "nsLayoutUtils.h"
 #include "nsStyleStruct.h"
 #include "Units.h"
 
 class gfxDrawable;
 namespace mozilla {
 
 namespace layers {
+class StackingContextHelper;
 class WebRenderParentCommand;
 class WebRenderDisplayItemLayer;
 } // namespace layers
 
 namespace wr {
 class DisplayListBuilder;
 } // namespace wr
 
@@ -203,16 +204,17 @@ public:
 
   /**
    * Builds WebRender DisplayItems for an image using
    * {background|mask}-specific arguments.
    * @see nsLayoutUtils::DrawImage() for parameters.
    */
   DrawResult BuildWebRenderDisplayItemsForLayer(nsPresContext*       aPresContext,
                                                 mozilla::wr::DisplayListBuilder& aBuilder,
+                                                const mozilla::layers::StackingContextHelper& aSc,
                                                 nsTArray<layers::WebRenderParentCommand>& aParentCommands,
                                                 mozilla::layers::WebRenderDisplayItemLayer* aLayer,
                                                 const nsRect&        aDest,
                                                 const nsRect&        aFill,
                                                 const nsPoint&       aAnchor,
                                                 const nsRect&        aDirty,
                                                 const nsSize&        aRepeatSize,
                                                 float                aOpacity);
@@ -287,16 +289,17 @@ private:
    * Builds WebRender DisplayItems for the image.
    * aSrc is a rect on the source image which will be mapped to aDest; it's
    * currently only used for gradients.
    *
    * @see nsLayoutUtils::DrawImage() for other parameters.
    */
   DrawResult BuildWebRenderDisplayItems(nsPresContext*       aPresContext,
                                         mozilla::wr::DisplayListBuilder& aBuilder,
+                                        const mozilla::layers::StackingContextHelper& aSc,
                                         nsTArray<layers::WebRenderParentCommand>& aParentCommands,
                                         mozilla::layers::WebRenderDisplayItemLayer* aLayer,
                                         const nsRect&        aDirtyRect,
                                         const nsRect&        aDest,
                                         const nsRect&        aFill,
                                         const nsPoint&       aAnchor,
                                         const nsSize&        aRepeatSize,
                                         const mozilla::CSSIntRect& aSrc,