--- a/layout/base/nsLayoutUtils.cpp
+++ b/layout/base/nsLayoutUtils.cpp
@@ -9174,35 +9174,35 @@ nsLayoutUtils::IsInvisibleBreak(nsINode*
     }
   }
 
   return lineNonEmpty;
 }
 
 static nsRect
 ComputeSVGReferenceRect(nsIFrame* aFrame,
-                        StyleClipPathGeometryBox aGeometryBox)
+                        StyleGeometryBox aGeometryBox)
 {
   MOZ_ASSERT(aFrame->GetContent()->IsSVGElement());
   nsRect r;
 
   // For SVG elements without associated CSS layout box, the used value for
   // content-box, padding-box, border-box and margin-box is fill-box.
   switch (aGeometryBox) {
-    case StyleClipPathGeometryBox::Stroke: {
+    case StyleGeometryBox::Stroke: {
       // XXX Bug 1299876
       // The size of srtoke-box is not correct if this graphic element has
       // specific stroke-linejoin or stroke-linecap.
       gfxRect bbox = nsSVGUtils::GetBBox(aFrame,
                 nsSVGUtils::eBBoxIncludeFill | nsSVGUtils::eBBoxIncludeStroke);
       r = nsLayoutUtils::RoundGfxRectToAppRect(bbox,
                                          nsPresContext::AppUnitsPerCSSPixel());
       break;
     }
-    case StyleClipPathGeometryBox::View: {
+    case StyleGeometryBox::View: {
       nsIContent* content = aFrame->GetContent();
       nsSVGElement* element = static_cast<nsSVGElement*>(content);
       SVGSVGElement* svgElement = element->GetCtx();
       MOZ_ASSERT(svgElement);
 
       if (svgElement && svgElement->HasViewBoxRect()) {
         // If a ‘viewBox‘ attribute is specified for the SVG viewport creating
         // element:
@@ -9222,78 +9222,78 @@ ComputeSVGReferenceRect(nsIFrame* aFrame
         svgFloatSize viewportSize = svgElement->GetViewportSize();
         r = nsRect(0, 0,
                    nsPresContext::CSSPixelsToAppUnits(viewportSize.width),
                    nsPresContext::CSSPixelsToAppUnits(viewportSize.height));
       }
 
       break;
     }
-    case StyleClipPathGeometryBox::NoBox:
-    case StyleClipPathGeometryBox::Border:
-    case StyleClipPathGeometryBox::Content:
-    case StyleClipPathGeometryBox::Padding:
-    case StyleClipPathGeometryBox::Margin:
-    case StyleClipPathGeometryBox::Fill: {
+    case StyleGeometryBox::NoBox:
+    case StyleGeometryBox::Border:
+    case StyleGeometryBox::Content:
+    case StyleGeometryBox::Padding:
+    case StyleGeometryBox::Margin:
+    case StyleGeometryBox::Fill: {
       gfxRect bbox = nsSVGUtils::GetBBox(aFrame,
                                          nsSVGUtils::eBBoxIncludeFill);
       r = nsLayoutUtils::RoundGfxRectToAppRect(bbox,
                                          nsPresContext::AppUnitsPerCSSPixel());
       break;
     }
     default:{
-      MOZ_ASSERT_UNREACHABLE("unknown StyleClipPathGeometryBox type");
+      MOZ_ASSERT_UNREACHABLE("unknown StyleGeometryBox type");
       gfxRect bbox = nsSVGUtils::GetBBox(aFrame,
                                          nsSVGUtils::eBBoxIncludeFill);
       r = nsLayoutUtils::RoundGfxRectToAppRect(bbox,
                                          nsPresContext::AppUnitsPerCSSPixel());
       break;
     }
   }
 
   return r;
 }
 
 static nsRect
 ComputeHTMLReferenceRect(nsIFrame* aFrame,
-                         StyleClipPathGeometryBox aGeometryBox)
+                         StyleGeometryBox aGeometryBox)
 {
   nsRect r;
 
   // For elements with associated CSS layout box, the used value for fill-box,
   // stroke-box and view-box is border-box.
   switch (aGeometryBox) {
-    case StyleClipPathGeometryBox::Content:
+    case StyleGeometryBox::Content:
       r = aFrame->GetContentRectRelativeToSelf();
       break;
-    case StyleClipPathGeometryBox::Padding:
+    case StyleGeometryBox::Padding:
       r = aFrame->GetPaddingRectRelativeToSelf();
       break;
-    case StyleClipPathGeometryBox::Margin:
+    case StyleGeometryBox::Margin:
       r = aFrame->GetMarginRectRelativeToSelf();
       break;
-    case StyleClipPathGeometryBox::NoBox:
-    case StyleClipPathGeometryBox::Border:
-    case StyleClipPathGeometryBox::Fill:
-    case StyleClipPathGeometryBox::Stroke:
-    case StyleClipPathGeometryBox::View:
+    case StyleGeometryBox::NoBox:
+    case StyleGeometryBox::Border:
+    case StyleGeometryBox::Fill:
+    case StyleGeometryBox::Stroke:
+    case StyleGeometryBox::View:
       r = aFrame->GetRectRelativeToSelf();
       break;
     default:
-      MOZ_ASSERT_UNREACHABLE("unknown StyleClipPathGeometryBox type");
+      MOZ_ASSERT_UNREACHABLE("unknown StyleGeometryBox type");
       r = aFrame->GetRectRelativeToSelf();
       break;
   }
 
   return r;
 }
 
 /* static */ nsRect
 nsLayoutUtils::ComputeGeometryBox(nsIFrame* aFrame,
-                                  StyleClipPathGeometryBox aGeometryBox)
+                                  StyleGeometryBox aGeometryBox)
 {
   // We use ComputeSVGReferenceRect for all SVG elements, except <svg>
   // element, which does have an associated CSS layout box. In this case we
   // should still use ComputeHTMLReferenceRect for region computing.
   nsRect r = aFrame->IsFrameOfType(nsIFrame::eSVG) &&
              (aFrame->GetType() != nsGkAtoms::svgOuterSVGFrame)
              ? ComputeSVGReferenceRect(aFrame, aGeometryBox)
              : ComputeHTMLReferenceRect(aFrame, aGeometryBox);

--- a/layout/base/nsLayoutUtils.h
+++ b/layout/base/nsLayoutUtils.h
@@ -147,17 +147,17 @@ public:
   typedef mozilla::layers::ScrollMetadata ScrollMetadata;
   typedef FrameMetrics::ViewID ViewID;
   typedef mozilla::CSSPoint CSSPoint;
   typedef mozilla::CSSSize CSSSize;
   typedef mozilla::CSSIntSize CSSIntSize;
   typedef mozilla::CSSRect CSSRect;
   typedef mozilla::ScreenMargin ScreenMargin;
   typedef mozilla::LayoutDeviceIntSize LayoutDeviceIntSize;
-  typedef mozilla::StyleClipPathGeometryBox StyleClipPathGeometryBox;
+  typedef mozilla::StyleGeometryBox StyleGeometryBox;
 
   /**
    * Finds previously assigned ViewID for the given content element, if any.
    * Returns whether a ViewID was previously assigned.
    */
   static bool FindIDFor(const nsIContent* aContent, ViewID* aOutViewId);
 
   /**
@@ -2866,17 +2866,17 @@ public:
    *          false if the node causes a visible break or if the node is no break.
    *
    * @param   aNextLineFrame  assigned to first frame on the next line if such a
    *                          next line exists, null otherwise.
    */
   static bool IsInvisibleBreak(nsINode* aNode, nsIFrame** aNextLineFrame = nullptr);
 
   static nsRect ComputeGeometryBox(nsIFrame* aFrame,
-                                   StyleClipPathGeometryBox aGeometryBox);
+                                   StyleGeometryBox aGeometryBox);
 
 private:
   static uint32_t sFontSizeInflationEmPerLine;
   static uint32_t sFontSizeInflationMinTwips;
   static uint32_t sFontSizeInflationLineThreshold;
   static int32_t  sFontSizeInflationMappingIntercept;
   static uint32_t sFontSizeInflationMaxRatio;
   static bool sFontSizeInflationForceEnabled;

--- a/layout/style/nsCSSProps.cpp
+++ b/layout/style/nsCSSProps.cpp
@@ -897,43 +897,43 @@ static_assert(NS_STYLE_IMAGELAYER_CLIP_B
 const KTableEntry nsCSSProps::kBackgroundOriginKTable[] = {
   { eCSSKeyword_border_box, NS_STYLE_IMAGELAYER_ORIGIN_BORDER },
   { eCSSKeyword_padding_box, NS_STYLE_IMAGELAYER_ORIGIN_PADDING },
   { eCSSKeyword_content_box, NS_STYLE_IMAGELAYER_ORIGIN_CONTENT },
   { eCSSKeyword_UNKNOWN, -1 }
 };
 
 KTableEntry nsCSSProps::kBackgroundClipKTable[] = {
-  { eCSSKeyword_border_box, NS_STYLE_IMAGELAYER_CLIP_BORDER },
-  { eCSSKeyword_padding_box, NS_STYLE_IMAGELAYER_CLIP_PADDING },
-  { eCSSKeyword_content_box, NS_STYLE_IMAGELAYER_CLIP_CONTENT },
+  { eCSSKeyword_border_box, StyleGeometryBox::Border },
+  { eCSSKeyword_padding_box, StyleGeometryBox::Padding },
+  { eCSSKeyword_content_box, StyleGeometryBox::Content },
   // The next entry is controlled by the layout.css.background-clip-text.enabled
   // pref.
-  { eCSSKeyword_text, NS_STYLE_IMAGELAYER_CLIP_TEXT },
+  { eCSSKeyword_text, StyleGeometryBox::Text },
   { eCSSKeyword_UNKNOWN, -1 }
 };
 
 const KTableEntry nsCSSProps::kMaskOriginKTable[] = {
   { eCSSKeyword_border_box, NS_STYLE_IMAGELAYER_ORIGIN_BORDER },
   { eCSSKeyword_padding_box, NS_STYLE_IMAGELAYER_ORIGIN_PADDING },
   { eCSSKeyword_content_box, NS_STYLE_IMAGELAYER_ORIGIN_CONTENT },
   { eCSSKeyword_fill_box, NS_STYLE_IMAGELAYER_ORIGIN_FILL },
   { eCSSKeyword_stroke_box, NS_STYLE_IMAGELAYER_ORIGIN_STROKE },
   { eCSSKeyword_view_box, NS_STYLE_IMAGELAYER_ORIGIN_VIEW },
   { eCSSKeyword_UNKNOWN, -1 }
 };
 
 const KTableEntry nsCSSProps::kMaskClipKTable[] = {
-  { eCSSKeyword_border_box, NS_STYLE_IMAGELAYER_CLIP_BORDER },
-  { eCSSKeyword_padding_box, NS_STYLE_IMAGELAYER_CLIP_PADDING },
-  { eCSSKeyword_content_box, NS_STYLE_IMAGELAYER_CLIP_CONTENT },
-  { eCSSKeyword_fill_box, NS_STYLE_IMAGELAYER_CLIP_FILL },
-  { eCSSKeyword_stroke_box, NS_STYLE_IMAGELAYER_CLIP_STROKE },
-  { eCSSKeyword_view_box, NS_STYLE_IMAGELAYER_CLIP_VIEW },
-  { eCSSKeyword_no_clip, NS_STYLE_IMAGELAYER_CLIP_NO_CLIP },
+  { eCSSKeyword_border_box, StyleGeometryBox::Border },
+  { eCSSKeyword_padding_box, StyleGeometryBox::Padding },
+  { eCSSKeyword_content_box, StyleGeometryBox::Content },
+  { eCSSKeyword_fill_box, StyleGeometryBox::Fill },
+  { eCSSKeyword_stroke_box, StyleGeometryBox::Stroke },
+  { eCSSKeyword_view_box, StyleGeometryBox::View },
+  { eCSSKeyword_no_clip, StyleGeometryBox::NoClip },
   { eCSSKeyword_UNKNOWN, -1 }
 };
 
 // Note: Don't change this table unless you update
 // ParseImageLayerPosition!
 
 const KTableEntry nsCSSProps::kImageLayerPositionKTable[] = {
   { eCSSKeyword_center, NS_STYLE_IMAGELAYER_POSITION_CENTER },
@@ -2298,23 +2298,23 @@ const KTableEntry nsCSSProps::kDominantB
 
 const KTableEntry nsCSSProps::kFillRuleKTable[] = {
   { eCSSKeyword_nonzero, StyleFillRule::Nonzero },
   { eCSSKeyword_evenodd, StyleFillRule::Evenodd },
   { eCSSKeyword_UNKNOWN, -1 }
 };
 
 const KTableEntry nsCSSProps::kClipPathGeometryBoxKTable[] = {
-  { eCSSKeyword_content_box, StyleClipPathGeometryBox::Content },
-  { eCSSKeyword_padding_box, StyleClipPathGeometryBox::Padding },
-  { eCSSKeyword_border_box, StyleClipPathGeometryBox::Border },
-  { eCSSKeyword_margin_box, StyleClipPathGeometryBox::Margin },
-  { eCSSKeyword_fill_box, StyleClipPathGeometryBox::Fill },
-  { eCSSKeyword_stroke_box, StyleClipPathGeometryBox::Stroke },
-  { eCSSKeyword_view_box, StyleClipPathGeometryBox::View },
+  { eCSSKeyword_content_box, StyleGeometryBox::Content },
+  { eCSSKeyword_padding_box, StyleGeometryBox::Padding },
+  { eCSSKeyword_border_box, StyleGeometryBox::Border },
+  { eCSSKeyword_margin_box, StyleGeometryBox::Margin },
+  { eCSSKeyword_fill_box, StyleGeometryBox::Fill },
+  { eCSSKeyword_stroke_box, StyleGeometryBox::Stroke },
+  { eCSSKeyword_view_box, StyleGeometryBox::View },
   { eCSSKeyword_UNKNOWN, -1 }
 };
 
 const KTableEntry nsCSSProps::kShapeRadiusKTable[] = {
   { eCSSKeyword_closest_side, StyleShapeRadius::ClosestSide },
   { eCSSKeyword_farthest_side, StyleShapeRadius::FarthestSide },
   { eCSSKeyword_UNKNOWN, -1 }
 };

--- a/layout/style/nsStyleConsts.h
+++ b/layout/style/nsStyleConsts.h
@@ -107,26 +107,45 @@ enum class StyleClear : uint8_t {
   InlineEnd,
   Both,
   // StyleClear::Line can be added to one of the other values in layout
   // so it needs to use a bit value that none of the other values can have.
   Line = 8,
   Max = 13  // Max = (Both | Line)
 };
 
-// clip-path geometry box
-enum class StyleClipPathGeometryBox : uint8_t {
-  NoBox,
+// Define geometry box for clip-path's reference-box, background-clip,
+// background-origin, mask-clip and mask-origin.
+enum class StyleGeometryBox : uint8_t {
   Content,
   Padding,
   Border,
-  Margin,
-  Fill,
-  Stroke,
-  View,
+  Margin,  // XXX Bug 1260094 comment 9.
+           // Although margin-box is required by mask-origin and mask-clip, we
+           // do not implement that due to lack of support in other browsers.
+           // clip-path reference-box only.
+  Fill,    // mask-clip, mask-origin and clip-path reference-box only.
+  Stroke,  // mask-clip, mask-origin and clip-path reference-box only.
+  View,    // mask-clip, mask-origin and clip-path reference-box only.
+  NoClip,  // mask-clip only.
+  Text,    // background-clip only.
+  NoBox,   // Depending on which kind of element this style value applied on,
+           // the default value of a reference-box can be different.
+           // For an HTML element, the default value of reference-box is
+           // border-box; for an SVG element, the default value is fill-box.
+           // Since we can not determine the default value at parsing time,
+           // set it as NoBox so that we make a decision later.
+           // clip-path reference-box only.
+  MozAlmostPadding = 127 // A magic value that we use for our "pretend that
+                         // background-clip is 'padding' when we have a solid
+                         // border" optimization.  This isn't actually equal
+                         // to StyleGeometryBox::Padding because using that
+                         // causes antialiasing seams between the background
+                         // and border.
+                         // background-clip only.
 };
 
 // fill-rule
 enum class StyleFillRule : uint8_t {
   Nonzero,
   Evenodd,
 };
 

--- a/layout/style/nsStyleStruct.h
+++ b/layout/style/nsStyleStruct.h
@@ -2746,17 +2746,17 @@ private:
   union {
     StyleBasicShape* mBasicShape;
     css::URLValue* mURL;
   };
   StyleShapeSourceType mType = StyleShapeSourceType::None;
   ReferenceBox mReferenceBox = ReferenceBox::NoBox;
 };
 
-using StyleClipPath = StyleShapeSource<StyleClipPathGeometryBox>;
+using StyleClipPath = StyleShapeSource<StyleGeometryBox>;
 using StyleShapeOutside = StyleShapeSource<StyleShapeOutsideShapeBox>;
 
 } // namespace mozilla
 
 struct MOZ_NEEDS_MEMMOVABLE_MEMBERS nsStyleDisplay
 {
   explicit nsStyleDisplay(StyleStructContext aContext);
   nsStyleDisplay(const nsStyleDisplay& aOther);