Subtree caching implementation in blink-core

Source/core/frame/FrameView.h

Index: Source/core/frame/FrameView.h
diff --git a/Source/core/frame/FrameView.h b/Source/core/frame/FrameView.h
index 37e884b2a50f5474b9ed80bce752c1a84d88df82..489864fb2363319cc80439b8238a87470c0aa3e8 100644
--- a/Source/core/frame/FrameView.h
+++ b/Source/core/frame/FrameView.h
@@ -599,6 +599,9 @@ protected:
     void invalidateTreeIfNeeded(PaintInvalidationState&);
 
 private:
+    friend class DisplayItemListPaintTestForSlimmingPaintV2;
+    friend class LayoutPart;

[chrishtr, 2015/08/27 04:29:48]

What is LayoutPart a friend for? Does this deserve a TODO to fix?

[Xianzhu, 2015/08/27 16:38:02]

Done.

+
     explicit FrameView(LocalFrame*);
 
     void setScrollOffset(const IntPoint&, ScrollType) override;
@@ -607,6 +610,7 @@ private:
     enum LifeCycleUpdateOption {
         AllPhases,
         OnlyUpToCompositingCleanPlusScrolling,
+        OnlyUpToPaintForSlimmingPaintV2Clean,
     };
 
     void updateLifecyclePhasesInternal(LifeCycleUpdateOption);
@@ -624,8 +628,6 @@ private:
     // Called when our frame rect changes (or the rect/scroll position of an ancestor changes).
     void frameRectsChanged() override;
 
-    friend class LayoutPart;
-
     bool contentsInCompositedLayer() const;
 
     void applyOverflowToViewport(LayoutObject*, ScrollbarMode& hMode, ScrollbarMode& vMode);