Calculate paint invalidation rect for scrollbars

third_party/WebKit/Source/core/layout/PaintInvalidationState.h

Index: third_party/WebKit/Source/core/layout/PaintInvalidationState.h
diff --git a/third_party/WebKit/Source/core/layout/PaintInvalidationState.h b/third_party/WebKit/Source/core/layout/PaintInvalidationState.h
index 53c2d7fffb1d0dcf4b5bc4a71d335c3244007d7b..73e629ca5c8380a6b56a6422f1664303f499e12f 100644
--- a/third_party/WebKit/Source/core/layout/PaintInvalidationState.h
+++ b/third_party/WebKit/Source/core/layout/PaintInvalidationState.h
@@ -53,6 +53,11 @@ public:
     void pushDelayedPaintInvalidationTarget(LayoutObject& obj) { m_pendingDelayedPaintInvalidations.append(&obj); }
     Vector<LayoutObject*>& pendingDelayedPaintInvalidationTargets() { return m_pendingDelayedPaintInvalidations; }
 
+    // Disable view clipping and scroll offset adjustment for paint invalidation of FrameView scrollbars.
+    // TODO(wangxianzhu): Remove this for root-layer-scrolls.

[chrishtr, 2015/11/17 01:34:20]

"Remove this when root-layer-scrolls launches"

[Xianzhu, 2015/11/17 18:31:37]

Done.

+    bool viewClippingAndScrollOffsetDisabled() const { return m_viewClippingAndScrollOffsetDisabled; }
+    void setViewClippingAndScrollOffsetDisabled(bool b) { m_viewClippingAndScrollOffsetDisabled = b; }
+
 private:
     PaintInvalidationState(const LayoutView&, Vector<LayoutObject*>& pendingDelayedPaintInvalidations, PaintInvalidationState* ownerPaintInvalidationState);
 
@@ -65,6 +70,7 @@ private:
     mutable bool m_cachedOffsetsEnabled;
     bool m_forcedSubtreeInvalidationWithinContainer;
     bool m_forcedSubtreeInvalidationRectUpdateWithinContainer;
+    bool m_viewClippingAndScrollOffsetDisabled;
 
     LayoutRect m_clipRect;