Fixed clip resize for document.rootScroller with inertTopControls

third_party/WebKit/Source/core/paint/PaintLayer.h

 /*
  * Copyright (C) 2003, 2009, 2012 Apple Inc. All rights reserved.
  * Copyright (C) 2013 Intel Corporation. All rights reserved.
  *
  * Portions are Copyright (C) 1998 Netscape Communications Corporation.
  *
  * Other contributors:
  *   Robert O'Callahan <roc+@cs.cmu.edu>
  *   David Baron <dbaron@fas.harvard.edu>
  *   Christian Biesinger <cbiesinger@web.de>
@@ skipping 916 matching lines @@
   }
   void setNeedsPaintPhaseDescendantOutlines() {
     DCHECK(isSelfPaintingLayer());
     m_needsPaintPhaseDescendantOutlines = true;
     m_previousPaintPhaseDescendantOutlinesWasEmpty = false;
   }
   void setPreviousPaintPhaseDescendantOutlinesEmpty(bool isEmpty) {
     m_previousPaintPhaseDescendantOutlinesWasEmpty = isEmpty;
   }
 
+  void setIsGlobalRootScroller(bool isGlobalRootScroller) {

[chrishtr, 2016/11/18 00:37:09]

Why set these here? Why not just change all call sites to query whether the
PaintLayer in question is the one mentioned by globalRootScrollerController()?
Not caching it here means it can't possibly get out of sync.

[bokan, 2016/11/18 22:30:35]

Yah, that's probably better. Fixed.

+    m_isGlobalRootScroller = isGlobalRootScroller;
+  }
+  bool isGlobalRootScroller() { return m_isGlobalRootScroller; }
+
   // Similar to above, but for PaintPhaseFloat.
   bool needsPaintPhaseFloat() const {
     return m_needsPaintPhaseFloat && !m_previousPaintPhaseFloatWasEmpty;
   }
   void setNeedsPaintPhaseFloat() {
     DCHECK(isSelfPaintingLayer());
     m_needsPaintPhaseFloat = true;
     m_previousPaintPhaseFloatWasEmpty = false;
   }
   void setPreviousPaintPhaseFloatEmpty(bool isEmpty) {
@@ skipping 220 matching lines @@
   static_assert(MaxPaintResult <= 2,
                 "Should update number of bits of m_previousPaintResult");
 
   unsigned m_needsPaintPhaseDescendantOutlines : 1;
   unsigned m_previousPaintPhaseDescendantOutlinesWasEmpty : 1;
   unsigned m_needsPaintPhaseFloat : 1;
   unsigned m_previousPaintPhaseFloatWasEmpty : 1;
   unsigned m_needsPaintPhaseDescendantBlockBackgrounds : 1;
   unsigned m_previousPaintPhaseDescendantBlockBackgroundsWasEmpty : 1;
 
+  unsigned m_isGlobalRootScroller : 1;
+
   // These bitfields are part of ancestor/descendant dependent compositing
   // inputs.
   unsigned m_hasDescendantWithClipPath : 1;
   unsigned m_hasNonIsolatedDescendantWithBlendMode : 1;
   unsigned m_hasAncestorWithClipPath : 1;
   unsigned m_hasRootScrollerAsDescendant : 1;
 
   LayoutBoxModelObject* m_layoutObject;
 
   PaintLayer* m_parent;
@@ skipping 37 matching lines @@
 
 }  // namespace blink
 
 #ifndef NDEBUG
 // Outside the WebCore namespace for ease of invocation from gdb.
 CORE_EXPORT void showLayerTree(const blink::PaintLayer*);
 CORE_EXPORT void showLayerTree(const blink::LayoutObject*);
 #endif
 
 #endif  // Layer_h