Optimize scroll adjustment for paint invalidation

third_party/WebKit/Source/core/layout/LayoutObject.cpp

 /*
  * Copyright (C) 1999 Lars Knoll (knoll@kde.org)
  *           (C) 1999 Antti Koivisto (koivisto@kde.org)
  *           (C) 2000 Dirk Mueller (mueller@kde.org)
  *           (C) 2004 Allan Sandfeld Jensen (kde@carewolf.com)
  * Copyright (C) 2004, 2005, 2006, 2007, 2008, 2011 Apple Inc.
  *               All rights reserved.
  * Copyright (C) 2009 Google Inc. All rights reserved.
  * Copyright (C) 2009 Torch Mobile Inc. All rights reserved.
  *               (http://www.torchmobile.com/)
@@ skipping 1094 matching lines @@
   // DisplayItemClient.
   ObjectPaintInvalidator(*this).invalidateDisplayItemClient(*this, reason);
 }
 
 bool LayoutObject::compositedScrollsWithRespectTo(
     const LayoutBoxModelObject& paintInvalidationContainer) const {
   return paintInvalidationContainer.usesCompositedScrolling() &&
          this != &paintInvalidationContainer;
 }
 
-IntSize LayoutObject::scrollAdjustmentForPaintInvalidation(
-    const LayoutBoxModelObject& paintInvalidationContainer) const {
-  // Non-composited scrolling should be included in the bounds of scrolled
-  // items. Since mapToVisualRectInAncestorSpace does not include scrolling of
-  // the ancestor, we need to add it back in after.
-  if (paintInvalidationContainer.isBox() &&
-      !paintInvalidationContainer.usesCompositedScrolling() &&
-      this != &paintInvalidationContainer) {
-    const LayoutBox* box = toLayoutBox(&paintInvalidationContainer);
-    if (box->hasOverflowClip())
-      return -box->scrolledContentOffset();
-  }
-  return IntSize();
-}
-
 LayoutRect LayoutObject::invalidatePaintRectangle(
     const LayoutRect& dirtyRect,
     DisplayItemClient* displayItemClient) const {
   return ObjectPaintInvalidator(*this).invalidatePaintRectangle(
       dirtyRect, displayItemClient);
 }
 
 void LayoutObject::invalidateTreeIfNeeded(
     const PaintInvalidationState& paintInvalidationState) {
   DCHECK(!RuntimeEnabledFeatures::slimmingPaintInvalidationEnabled());
@@ skipping 2485 matching lines @@
     const blink::LayoutObject* root = object1;
     while (root->parent())
       root = root->parent();
     root->showLayoutTreeAndMark(object1, "*", object2, "-", 0);
   } else {
     WTFLogAlways("%s", "Cannot showLayoutTree. Root is (nil)");
   }
 }
 
 #endif