Remove assorted dead paint invalidation code.

sky/engine/core/frame/FrameView.h

Index: sky/engine/core/frame/FrameView.h
diff --git a/sky/engine/core/frame/FrameView.h b/sky/engine/core/frame/FrameView.h
index 732884dd98e65b90769ecdcb88d9dd5dc130f23e..9c7adf182c1f64f8e5d38f6bb049792966dea8d4 100644
--- a/sky/engine/core/frame/FrameView.h
+++ b/sky/engine/core/frame/FrameView.h
@@ -191,7 +191,6 @@ public:
     // FIXME(sky): Not clear what values these should return. This is just what they happen to be
     // returning today.
     bool paintsEntireContents() const { return false; }
-    bool clipsPaintInvalidations() const { return true; }
 
     // For inspector reporting:
     void countObjectsNeedingLayout(unsigned& needsLayoutObjects, unsigned& totalObjects, bool& isPartial);