End-to-end prototype of compositor scrolling with slimming paint v2

third_party/WebKit/Source/platform/graphics/compositing/PaintArtifactCompositor.h

Index: third_party/WebKit/Source/platform/graphics/compositing/PaintArtifactCompositor.h
diff --git a/third_party/WebKit/Source/platform/graphics/compositing/PaintArtifactCompositor.h b/third_party/WebKit/Source/platform/graphics/compositing/PaintArtifactCompositor.h
index 50aed967eb27513a481fe7e6816be1f6c0abac32..953766f0407ec1cef191d31c273407df38a78ed3 100644
--- a/third_party/WebKit/Source/platform/graphics/compositing/PaintArtifactCompositor.h
+++ b/third_party/WebKit/Source/platform/graphics/compositing/PaintArtifactCompositor.h
@@ -5,15 +5,16 @@
 #ifndef PaintArtifactCompositor_h
 #define PaintArtifactCompositor_h
 
+#include <memory>
 #include "base/memory/ref_counted.h"
 #include "platform/PlatformExport.h"
 #include "platform/RuntimeEnabledFeatures.h"
 #include "platform/graphics/GraphicsLayerClient.h"
 #include "platform/graphics/paint/PaintController.h"
+#include "public/platform/WebLayerScrollClient.h"
 #include "wtf/Noncopyable.h"
 #include "wtf/PtrUtil.h"
 #include "wtf/Vector.h"
-#include <memory>
 
 namespace cc {
 class DisplayItemList;
@@ -49,6 +50,9 @@ class PLATFORM_EXPORT PaintArtifactCompositor {
     return WTF::wrapUnique(new PaintArtifactCompositor());
   }
 
+  using ScrollClientMap =
+      HashMap<const ScrollPaintPropertyNode*, WebLayerScrollClient*>;
+
   // Updates the layer tree to match the provided paint artifact.
   // If |storeDebugInfo| is true, stores detailed debugging information in
   // the layers that will be output as part of a call to layersAsJSON
@@ -57,7 +61,8 @@ class PLATFORM_EXPORT PaintArtifactCompositor {
       const PaintArtifact&,
       RasterInvalidationTrackingMap<const PaintChunk>* paintChunkInvalidations,
       bool storeDebugInfo,
-      GeometryMapper&);
+      GeometryMapper&,
+      ScrollClientMap&);
 
   // The root layer of the tree managed by this object.
   cc::Layer* rootLayer() const { return m_rootLayer.get(); }