Initial scroll-blocks-on compositor integration

public/platform/WebLayer.h

Index: public/platform/WebLayer.h
diff --git a/public/platform/WebLayer.h b/public/platform/WebLayer.h
index 5d3bac1b7bda48f468b4aee6bb75af0019b6920b..74bf4978e4e0f83a0095f5f457519a45f76952b6 100644
--- a/public/platform/WebLayer.h
+++ b/public/platform/WebLayer.h
@@ -34,6 +34,7 @@
 #include "WebFloatPoint3D.h"
 #include "WebPoint.h"
 #include "WebRect.h"
+#include "WebScrollBlocksOn.h"
 #include "WebSize.h"
 #include "WebString.h"
 #include "WebVector.h"
@@ -186,6 +187,10 @@ public:
     virtual void setTouchEventHandlerRegion(const WebVector<WebRect>&) = 0;
     virtual WebVector<WebRect> touchEventHandlerRegion() const = 0;
 
+    // FIXME: Make pure once cc is updated.  crbug.com/347272
+    virtual void setScrollBlocksOn(WebScrollBlocksOn) { };
+    virtual WebScrollBlocksOn scrollBlocksOn() const { return WebScrollBlocksOnNone;};
+
     virtual void setIsContainerForFixedPositionLayers(bool) = 0;
     virtual bool isContainerForFixedPositionLayers() const = 0;