Invalidate the bigger rect if one rect contains the other in LayoutObject::fullyInvalidateRect()

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/)
  *
  * This library is free software; you can redistribute it and/or
@@ skipping 1558 matching lines @@
         invalidatePaintUsingContainer(paintInvalidationContainer, invalidationRect, PaintInvalidationIncremental);
     } else if (deltaBottom < 0) {
         LayoutRect invalidationRect(oldBounds.x(), newBounds.maxY(), oldBounds.width(), -deltaBottom);
         adjustInvalidationRectForCompositedScrolling(invalidationRect, paintInvalidationContainer);
         invalidatePaintUsingContainer(paintInvalidationContainer, invalidationRect, PaintInvalidationIncremental);
     }
 }
 
 void LayoutObject::fullyInvalidatePaint(const LayoutBoxModelObject& paintInvalidationContainer, PaintInvalidationReason invalidationReason, const LayoutRect& oldBounds, const LayoutRect& newBounds)
 {
-    // Otherwise do full paint invalidation.
-    LayoutRect invalidationRect = oldBounds;
+    // The following logic avoids invalidating twice if one set of bounds contains the other.
+    if (!newBounds.contains(oldBounds)) {
+        LayoutRect invalidationRect = oldBounds;
+        adjustInvalidationRectForCompositedScrolling(invalidationRect, paintInvalidationContainer);
+        invalidatePaintUsingContainer(paintInvalidationContainer, invalidationRect, invalidationReason);
+
+        if (oldBounds.contains(newBounds))
+            return;
+    }
+
+    LayoutRect invalidationRect = newBounds;
     adjustInvalidationRectForCompositedScrolling(invalidationRect, paintInvalidationContainer);
     invalidatePaintUsingContainer(paintInvalidationContainer, invalidationRect, invalidationReason);
-    if (newBounds != oldBounds) {
-        invalidationRect = newBounds;
-        adjustInvalidationRectForCompositedScrolling(invalidationRect, paintInvalidationContainer);
-        invalidatePaintUsingContainer(paintInvalidationContainer, invalidationRect, invalidationReason);
-    }
 }
 
 void LayoutObject::invalidatePaintForOverflow()
 {
 }
 
 void LayoutObject::invalidatePaintForOverflowIfNeeded()
 {
     if (shouldInvalidateOverflowForPaint())
         invalidatePaintForOverflow();
@@ skipping 2076 matching lines @@
         const blink::LayoutObject* root = object1;
         while (root->parent())
             root = root->parent();
         root->showLayoutTreeAndMark(object1, "*", object2, "-", 0);
     } else {
         fprintf(stderr, "Cannot showLayoutTree. Root is (nil)\n");
     }
 }
 
 #endif