--- a/dom/base/CharacterData.cpp
+++ b/dom/base/CharacterData.cpp
@@ -32,16 +32,17 @@
 #include "mozilla/dom/DirectionalityUtils.h"
 #include "nsBindingManager.h"
 #include "nsCCUncollectableMarker.h"
 #include "mozAutoDocUpdate.h"
 #include "nsTextNode.h"
 #include "nsBidiUtils.h"
 #include "PLDHashTable.h"
 #include "mozilla/Sprintf.h"
+#include "nsWindowSizes.h"
 #include "nsWrapperCacheInlines.h"
 
 namespace mozilla {
 namespace dom {
 
 CharacterData::CharacterData(already_AddRefed<dom::NodeInfo>& aNodeInfo)
   : nsIContent(aNodeInfo)
 {

--- a/dom/base/Element.cpp
+++ b/dom/base/Element.cpp
@@ -74,16 +74,17 @@
 #include "mozilla/TextEditor.h"
 #include "mozilla/TextEvents.h"
 #include "nsNodeUtils.h"
 #include "mozilla/dom/DirectionalityUtils.h"
 #include "nsDocument.h"
 #include "nsAttrValueOrString.h"
 #include "nsAttrValueInlines.h"
 #include "nsCSSPseudoElements.h"
+#include "nsWindowSizes.h"
 #ifdef MOZ_XUL
 #include "nsXULElement.h"
 #endif /* MOZ_XUL */
 #include "nsSVGElement.h"
 #include "nsFrameSelection.h"
 #ifdef DEBUG
 #include "nsRange.h"
 #endif

--- a/dom/base/FragmentOrElement.cpp
+++ b/dom/base/FragmentOrElement.cpp
@@ -79,16 +79,17 @@
 #include "nsPIDOMWindow.h"
 #include "nsPIBoxObject.h"
 #include "nsSVGUtils.h"
 #include "nsLayoutUtils.h"
 #include "nsGkAtoms.h"
 #include "nsContentUtils.h"
 #include "nsTextFragment.h"
 #include "nsContentCID.h"
+#include "nsWindowSizes.h"
 
 #include "nsIDOMEventListener.h"
 #include "nsIWebNavigation.h"
 #include "nsIBaseWindow.h"
 #include "nsIWidget.h"
 
 #include "nsNodeInfoManager.h"
 #include "nsICategoryManager.h"

--- a/dom/base/Link.h
+++ b/dom/base/Link.h
@@ -13,16 +13,17 @@
 
 #include "mozilla/MemoryReporting.h"
 #include "nsIContent.h" // for nsLinkState
 #include "nsIContentPolicy.h"
 
 namespace mozilla {
 
 class EventStates;
+class SizeOfState;
 
 namespace dom {
 
 class Element;
 
 #define MOZILLA_DOM_LINK_IMPLEMENTATION_IID               \
 { 0xb25edee6, 0xdd35, 0x4f8b,                             \
   { 0xab, 0x90, 0x66, 0xd0, 0xbd, 0x3c, 0x22, 0xd5 } }

--- a/dom/base/nsINode.cpp
+++ b/dom/base/nsINode.cpp
@@ -2400,16 +2400,23 @@ nsINode::AddSizeOfExcludingThis(nsWindow
   // - mNodeInfo
   // - mSlots
   //
   // The following members are not measured:
   // - mParent, mNextSibling, mPreviousSibling, mFirstChild: because they're
   //   non-owning
 }
 
+void
+nsINode::AddSizeOfIncludingThis(nsWindowSizes& aSizes, size_t* aNodeSize) const
+{
+  *aNodeSize += aSizes.mState.mMallocSizeOf(this);
+  AddSizeOfExcludingThis(aSizes, aNodeSize);
+}
+
 #define EVENT(name_, id_, type_, struct_)                                    \
   EventHandlerNonNull* nsINode::GetOn##name_() {                             \
     EventListenerManager *elm = GetExistingListenerManager();                \
     return elm ? elm->GetEventHandler(nsGkAtoms::on##name_, EmptyString())   \
                : nullptr;                                                    \
   }                                                                          \
   void nsINode::SetOn##name_(EventHandlerNonNull* handler)                   \
   {                                                                          \

--- a/dom/base/nsINode.h
+++ b/dom/base/nsINode.h
@@ -12,17 +12,16 @@
 #include "nsCOMPtr.h"               // for member, local
 #include "nsGkAtoms.h"              // for nsGkAtoms::baseURIProperty
 #include "nsIDOMNode.h"
 #include "mozilla/dom/NodeInfo.h"            // member (in nsCOMPtr)
 #include "nsIVariant.h"             // for use in GetUserData()
 #include "nsNodeInfoManager.h"      // for use in NodePrincipal()
 #include "nsPropertyTable.h"        // for typedefs
 #include "nsTObserverArray.h"       // for member
-#include "nsWindowSizes.h"          // for nsStyleSizes
 #include "mozilla/ErrorResult.h"
 #include "mozilla/LinkedList.h"
 #include "mozilla/MemoryReporting.h"
 #include "mozilla/dom/EventTarget.h" // for base class
 #include "js/TypeDecls.h"     // for Handle, Value, JSObject, JSContext
 #include "mozilla/dom/DOMString.h"
 #include "mozilla/dom/BindingDeclarations.h"
 #include "mozilla/dom/NodeBinding.h"
@@ -51,16 +50,17 @@ class nsINode;
 class nsINodeList;
 class nsIPresShell;
 class nsIPrincipal;
 class nsIURI;
 class nsNodeSupportsWeakRefTearoff;
 class nsNodeWeakReference;
 class nsDOMMutationObserver;
 class nsRange;
+class nsWindowSizes;
 struct RawServoSelectorList;
 
 namespace mozilla {
 class EventListenerManager;
 class TextEditor;
 namespace dom {
 /**
  * @return true if aChar is what the WHATWG defines as a 'ascii whitespace'.
@@ -354,21 +354,17 @@ public:
   virtual void AddSizeOfExcludingThis(nsWindowSizes& aSizes,
                                       size_t* aNodeSize) const;
 
   // SizeOfIncludingThis doesn't need to be overridden by sub-classes because
   // sub-classes of nsINode are guaranteed to be laid out in memory in such a
   // way that |this| points to the start of the allocated object, even in
   // methods of nsINode's sub-classes, so aSizes.mState.mMallocSizeOf(this) is
   // always safe to call no matter which object it was invoked on.
-  virtual void AddSizeOfIncludingThis(nsWindowSizes& aSizes,
-                                      size_t* aNodeSize) const {
-    *aNodeSize += aSizes.mState.mMallocSizeOf(this);
-    AddSizeOfExcludingThis(aSizes, aNodeSize);
-  }
+  void AddSizeOfIncludingThis(nsWindowSizes& aSizes, size_t* aNodeSize) const;
 
   friend class nsNodeUtils;
   friend class nsNodeWeakReference;
   friend class nsNodeSupportsWeakRefTearoff;
   friend class nsAttrAndChildArray;
 
 #ifdef MOZILLA_INTERNAL_API
   explicit nsINode(already_AddRefed<mozilla::dom::NodeInfo>& aNodeInfo)

--- a/dom/html/HTMLAnchorElement.cpp
+++ b/dom/html/HTMLAnchorElement.cpp
@@ -14,16 +14,17 @@
 #include "nsContentUtils.h"
 #include "nsGkAtoms.h"
 #include "nsHTMLDNSPrefetch.h"
 #include "nsAttrValueOrString.h"
 #include "nsIDocument.h"
 #include "nsIPresShell.h"
 #include "nsPresContext.h"
 #include "nsIURI.h"
+#include "nsWindowSizes.h"
 
 NS_IMPL_NS_NEW_HTML_ELEMENT(Anchor)
 
 namespace mozilla {
 namespace dom {
 
 #define ANCHOR_ELEMENT_FLAG_BIT(n_) NODE_FLAG_BIT(ELEMENT_TYPE_SPECIFIC_BITS_OFFSET + (n_))
 

--- a/dom/html/HTMLAreaElement.cpp
+++ b/dom/html/HTMLAreaElement.cpp
@@ -7,16 +7,17 @@
 #include "mozilla/dom/HTMLAreaElement.h"
 
 #include "mozilla/Attributes.h"
 #include "mozilla/dom/HTMLAnchorElement.h"
 #include "mozilla/dom/HTMLAreaElementBinding.h"
 #include "mozilla/EventDispatcher.h"
 #include "mozilla/EventStates.h"
 #include "mozilla/MemoryReporting.h"
+#include "nsWindowSizes.h"
 
 NS_IMPL_NS_NEW_HTML_ELEMENT(Area)
 
 namespace mozilla {
 namespace dom {
 
 HTMLAreaElement::HTMLAreaElement(already_AddRefed<mozilla::dom::NodeInfo>& aNodeInfo)
   : nsGenericHTMLElement(aNodeInfo)

--- a/dom/html/HTMLLinkElement.cpp
+++ b/dom/html/HTMLLinkElement.cpp
@@ -23,16 +23,17 @@
 #include "nsINode.h"
 #include "nsIStyleSheetLinkingElement.h"
 #include "nsIURL.h"
 #include "nsPIDOMWindow.h"
 #include "nsReadableUtils.h"
 #include "nsStyleConsts.h"
 #include "nsStyleLinkElement.h"
 #include "nsUnicharUtils.h"
+#include "nsWindowSizes.h"
 
 #define LINK_ELEMENT_FLAG_BIT(n_) \
   NODE_FLAG_BIT(ELEMENT_TYPE_SPECIFIC_BITS_OFFSET + (n_))
 
 // Link element specific bits
 enum {
   // Indicates that a DNS Prefetch has been requested from this Link element.
   HTML_LINK_DNS_PREFETCH_REQUESTED = LINK_ELEMENT_FLAG_BIT(0),

--- a/dom/svg/SVGPathElement.cpp
+++ b/dom/svg/SVGPathElement.cpp
@@ -15,16 +15,17 @@
 #include "mozilla/dom/SVGPathElementBinding.h"
 #include "mozilla/gfx/2D.h"
 #include "mozilla/RefPtr.h"
 #include "nsCOMPtr.h"
 #include "nsComputedDOMStyle.h"
 #include "nsGkAtoms.h"
 #include "nsStyleConsts.h"
 #include "nsStyleStruct.h"
+#include "nsWindowSizes.h"
 #include "SVGContentUtils.h"
 
 NS_IMPL_NS_NEW_NAMESPACED_SVG_ELEMENT(Path)
 
 using namespace mozilla::gfx;
 
 namespace mozilla {
 namespace dom {

--- a/dom/xbl/nsXBLDocumentInfo.cpp
+++ b/dom/xbl/nsXBLDocumentInfo.cpp
@@ -18,16 +18,17 @@
 #include "nsIConsoleService.h"
 #include "nsIScriptError.h"
 #include "nsIChromeRegistry.h"
 #include "nsIPrincipal.h"
 #include "nsJSPrincipals.h"
 #include "nsIScriptSecurityManager.h"
 #include "nsContentUtils.h"
 #include "nsDOMJSUtils.h"
+#include "nsWindowSizes.h"
 #include "mozilla/Services.h"
 #include "xpcpublic.h"
 #include "mozilla/scache/StartupCache.h"
 #include "mozilla/scache/StartupCacheUtils.h"
 #include "nsCCUncollectableMarker.h"
 #include "mozilla/dom/BindingUtils.h"
 #include "mozilla/dom/URL.h"
 

--- a/image/Image.cpp
+++ b/image/Image.cpp
@@ -1,16 +1,17 @@
 /* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
 /* This Source Code Form is subject to the terms of the Mozilla Public
  * License, v. 2.0. If a copy of the MPL was not distributed with this
  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
 
 #include "Image.h"
 #include "Layers.h"               // for LayerManager
 #include "nsRefreshDriver.h"
+#include "mozilla/SizeOfState.h"
 #include "mozilla/TimeStamp.h"
 #include "mozilla/Tuple.h"        // for Tie
 
 namespace mozilla {
 namespace image {
 
 ///////////////////////////////////////////////////////////////////////////////
 // Memory Reporting

--- a/image/RasterImage.cpp
+++ b/image/RasterImage.cpp
@@ -33,16 +33,17 @@
 
 #include "mozilla/gfx/2D.h"
 #include "mozilla/DebugOnly.h"
 #include "mozilla/Likely.h"
 #include "mozilla/RefPtr.h"
 #include "mozilla/Move.h"
 #include "mozilla/MemoryReporting.h"
 #include "mozilla/Services.h"
+#include "mozilla/SizeOfState.h"
 #include <stdint.h>
 #include "mozilla/Telemetry.h"
 #include "mozilla/TimeStamp.h"
 #include "mozilla/Tuple.h"
 #include "mozilla/ClearOnShutdown.h"
 #include "mozilla/gfx/Scale.h"
 
 #include "GeckoProfiler.h"

--- a/js/xpconnect/src/XPCJSRuntime.cpp
+++ b/js/xpconnect/src/XPCJSRuntime.cpp
@@ -22,16 +22,17 @@
 #include "nsIMemoryInfoDumper.h"
 #include "nsIMemoryReporter.h"
 #include "nsIObserverService.h"
 #include "nsIDebug2.h"
 #include "nsIDocShell.h"
 #include "nsIRunnable.h"
 #include "nsPIDOMWindow.h"
 #include "nsPrintfCString.h"
+#include "nsWindowSizes.h"
 #include "mozilla/Preferences.h"
 #include "mozilla/Telemetry.h"
 #include "mozilla/Services.h"
 #include "mozilla/dom/ScriptLoader.h"
 #include "mozilla/dom/ScriptSettings.h"
 
 #include "nsContentUtils.h"
 #include "nsCCUncollectableMarker.h"

--- a/layout/base/nsFrameManager.cpp
+++ b/layout/base/nsFrameManager.cpp
@@ -25,16 +25,17 @@
 #include "nsError.h"
 #include "nsAutoPtr.h"
 #include "nsAbsoluteContainingBlock.h"
 #include "ChildIterator.h"
 
 #include "GeckoProfiler.h"
 #include "nsIStatefulFrame.h"
 #include "nsContainerFrame.h"
+#include "nsWindowSizes.h"
 
 #include "mozilla/MemoryReporting.h"
 
 // #define DEBUG_UNDISPLAYED_MAP
 // #define DEBUG_DISPLAY_CONTENTS_MAP
 
 using namespace mozilla;
 using namespace mozilla::dom;

--- a/layout/generic/nsFrame.cpp
+++ b/layout/generic/nsFrame.cpp
@@ -89,16 +89,17 @@
 #include "gfxContext.h"
 #include "gfxPrefs.h"
 #include "nsAbsoluteContainingBlock.h"
 #include "StickyScrollContainer.h"
 #include "nsFontInflationData.h"
 #include "nsRegion.h"
 #include "nsIFrameInlines.h"
 #include "nsStyleChangeList.h"
+#include "nsWindowSizes.h"
 
 #include "mozilla/AsyncEventDispatcher.h"
 #include "mozilla/EffectCompositor.h"
 #include "mozilla/EffectSet.h"
 #include "mozilla/EventListenerManager.h"
 #include "mozilla/EventStateManager.h"
 #include "mozilla/EventStates.h"
 #include "mozilla/Preferences.h"

--- a/layout/style/CachedInheritingStyles.cpp
+++ b/layout/style/CachedInheritingStyles.cpp
@@ -4,16 +4,17 @@
  * License, v. 2.0. If a copy of the MPL was not distributed with this
  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
 
 #include "mozilla/CachedInheritingStyles.h"
 
 #include "mozilla/ComputedStyle.h"
 #include "nsCOMPtr.h"
 #include "nsIMemoryReporter.h"
+#include "nsWindowSizes.h"
 
 namespace mozilla {
 
 void
 CachedInheritingStyles::Insert(ComputedStyle* aStyle)
 {
   MOZ_ASSERT(aStyle);
   MOZ_ASSERT(aStyle->IsInheritingAnonBox() || aStyle->IsLazilyCascadedPseudoElement());

--- a/layout/style/ComputedStyle.cpp
+++ b/layout/style/ComputedStyle.cpp
@@ -13,16 +13,17 @@
 #include "nsCSSAnonBoxes.h"
 #include "nsCSSPseudoElements.h"
 #include "nsFontMetrics.h"
 #include "nsStyleConsts.h"
 #include "nsStyleStruct.h"
 #include "nsStyleStructInlines.h"
 #include "nsString.h"
 #include "nsPresContext.h"
+#include "nsWindowSizes.h"
 
 #include "nsCOMPtr.h"
 #include "nsIPresShell.h"
 
 #include "GeckoProfiler.h"
 #include "nsIDocument.h"
 #include "nsPrintfCString.h"
 #include "RubyUtils.h"
@@ -490,9 +491,22 @@ ComputedStyle::GetCachedLazyPseudoStyle(
 
   if (nsCSSPseudoElements::PseudoElementSupportsUserActionState(aPseudo)) {
     return nullptr;
   }
 
   return mCachedInheritingStyles.Lookup(nsCSSPseudoElements::GetPseudoAtom(aPseudo));
 }
 
+void
+ComputedStyle::AddSizeOfIncludingThis(nsWindowSizes& aSizes,
+                                      size_t* aCVsSize) const
+{
+  // Note: |this| sits within a servo_arc::Arc, i.e. it is preceded by a
+  // refcount. So we need to measure it with a function that can handle an
+  // interior pointer. We use ServoComputedValuesMallocEnclosingSizeOf to
+  // clearly identify in DMD's output the memory measured here.
+  *aCVsSize += ServoComputedValuesMallocEnclosingSizeOf(this);
+  mSource.AddSizeOfExcludingThis(aSizes);
+  mCachedInheritingStyles.AddSizeOfIncludingThis(aSizes, aCVsSize);
+}
+
 } // namespace mozilla

--- a/layout/style/ComputedStyle.h
+++ b/layout/style/ComputedStyle.h
@@ -5,28 +5,28 @@
  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
 
 /* the interface (to internal code) for retrieving computed style data */
 
 #ifndef _ComputedStyle_h_
 #define _ComputedStyle_h_
 
 #include "nsIMemoryReporter.h"
-#include "nsWindowSizes.h"
 #include <algorithm>
 #include "mozilla/Assertions.h"
 #include "mozilla/RestyleLogging.h"
 #include "mozilla/ServoStyleSet.h"
 #include "mozilla/ServoUtils.h"
 #include "mozilla/StyleComplexColor.h"
 #include "mozilla/CachedInheritingStyles.h"
 #include "nsCSSAnonBoxes.h"
 
 class nsAtom;
 class nsPresContext;
+class nsWindowSizes;
 
 namespace mozilla {
 
 enum class CSSPseudoElementType : uint8_t;
 class ComputedStyle;
 
 extern "C" {
   void Servo_ComputedStyle_AddRef(const mozilla::ComputedStyle* aStyle);
@@ -345,26 +345,17 @@ public:
    * Makes this context match |aOther| in terms of which style structs have
    * been resolved.
    */
   inline void ResolveSameStructsAs(const ComputedStyle* aOther);
 
   // The |aCVsSize| outparam on this function is where the actual CVs size
   // value is added. It's done that way because the callers know which value
   // the size should be added to.
-  void AddSizeOfIncludingThis(nsWindowSizes& aSizes, size_t* aCVsSize) const
-  {
-    // Note: |this| sits within a servo_arc::Arc, i.e. it is preceded by a
-    // refcount. So we need to measure it with a function that can handle an
-    // interior pointer. We use ServoComputedValuesMallocEnclosingSizeOf to
-    // clearly identify in DMD's output the memory measured here.
-    *aCVsSize += ServoComputedValuesMallocEnclosingSizeOf(this);
-    mSource.AddSizeOfExcludingThis(aSizes);
-    mCachedInheritingStyles.AddSizeOfIncludingThis(aSizes, aCVsSize);
-  }
+  void AddSizeOfIncludingThis(nsWindowSizes& aSizes, size_t* aCVsSize) const;
 
   // Needs to be public so that we can call it from Servo.
   ~ComputedStyle() = default;
 
 protected:
 
   nsPresContext* mPresContext;
 

--- a/layout/style/ServoBindings.cpp
+++ b/layout/style/ServoBindings.cpp
@@ -41,16 +41,17 @@
 #include "nsNameSpaceManager.h"
 #include "nsNetUtil.h"
 #include "nsString.h"
 #include "nsStyleStruct.h"
 #include "nsStyleUtil.h"
 #include "nsSVGElement.h"
 #include "nsTArray.h"
 #include "nsTransitionManager.h"
+#include "nsWindowSizes.h"
 
 #include "mozilla/CORSMode.h"
 #include "mozilla/DeclarationBlockInlines.h"
 #include "mozilla/EffectCompositor.h"
 #include "mozilla/EffectSet.h"
 #include "mozilla/EventStates.h"
 #include "mozilla/Keyframe.h"
 #include "mozilla/Mutex.h"

--- a/layout/style/ServoStyleSet.cpp
+++ b/layout/style/ServoStyleSet.cpp
@@ -31,16 +31,17 @@
 #include "nsIAnonymousContentCreator.h"
 #include "nsIDocumentInlines.h"
 #include "nsMediaFeatures.h"
 #include "nsPrintfCString.h"
 #include "nsSMILAnimationController.h"
 #include "nsXBLPrototypeBinding.h"
 #include "gfxUserFontSet.h"
 #include "nsBindingManager.h"
+#include "nsWindowSizes.h"
 
 using namespace mozilla;
 using namespace mozilla::dom;
 
 #ifdef DEBUG
 bool
 ServoStyleSet::IsCurrentThreadInServoTraversal()
 {