Remove background obscuration checks.

sky/engine/core/rendering/style/RenderStyle.cpp

 /*
  * Copyright (C) 1999 Antti Koivisto (koivisto@kde.org)
  * Copyright (C) 2004, 2005, 2006, 2007, 2008, 2009, 2010 Apple Inc. All rights reserved.
  * Copyright (C) 2011 Adobe Systems Incorporated. All rights reserved.
  *
  * This library is free software; you can redistribute it and/or
  * modify it under the terms of the GNU Library General Public
  * License as published by the Free Software Foundation; either
  * version 2 of the License, or (at your option) any later version.
  *
@@ skipping 281 matching lines @@
         diff.setNeedsFullLayout();
 
     if (!diff.needsFullLayout() && position() != StaticPosition && surround->offset != other.surround->offset) {
         // Optimize for the case where a positioned layer is moving but not changing size.
         if (positionedObjectMovedOnly(surround->offset, other.surround->offset, m_box->width()))
             diff.setNeedsPositionedMovementLayout();
         else
             diff.setNeedsFullLayout();
     }
 
-    if (!diff.needsFullLayout() && diffNeedsPaintInvalidation(other))
-        diff.setNeedsPaintInvalidation();
-
     updatePropertySpecificDifferences(other, diff);
 
     // Cursors are not checked, since they will be set appropriately in response to mouse events,
     // so they don't need to cause any paint invalidation or layout.
 
     // Animations don't need to be checked either. We always set the new style on the RenderObject, so we will get a chance to fire off
     // the resulting transition properly.
 
     return diff;
 }
@@ skipping 140 matching lines @@
         if (surround->margin != other.surround->margin)
             return true;
 
         if (surround->padding != other.surround->padding)
             return true;
     }
 
     return false;
 }
 
-bool RenderStyle::diffNeedsPaintInvalidation(const RenderStyle& other) const
-{
-    if (inherited_flags._visibility != other.inherited_flags._visibility
-        || !surround->border.visuallyEqual(other.surround->border)
-        || !m_background->visuallyEqual(*other.m_background))
-        return true;
-
-    if (rareInheritedData.get() != other.rareInheritedData.get()) {
-        if (rareInheritedData->userModify != other.rareInheritedData->userModify
-            || rareInheritedData->userSelect != other.rareInheritedData->userSelect
-            || rareInheritedData->m_imageRendering != other.rareInheritedData->m_imageRendering)
-            return true;
-    }
-
-    if (rareNonInheritedData.get() != other.rareNonInheritedData.get()) {
-        if (rareNonInheritedData->userDrag != other.rareNonInheritedData->userDrag
-            || rareNonInheritedData->m_objectFit != other.rareNonInheritedData->m_objectFit
-            || rareNonInheritedData->m_objectPosition != other.rareNonInheritedData->m_objectPosition
-            || !dataEquivalent(rareNonInheritedData->m_clipPath, other.rareNonInheritedData->m_clipPath))
-            return true;
-    }
-
-    if (position() != StaticPosition && (visual->clip != other.visual->clip || visual->hasAutoClip != other.visual->hasAutoClip))
-        return true;
-
-    if (rareNonInheritedData.get() != other.rareNonInheritedData.get()) {
-        if (rareNonInheritedData->m_mask != other.rareNonInheritedData->m_mask
-            || rareNonInheritedData->m_maskBoxImage != other.rareNonInheritedData->m_maskBoxImage)
-            return true;
-    }
-
-    return false;
-}
-
 void RenderStyle::updatePropertySpecificDifferences(const RenderStyle& other, StyleDifference& diff) const
 {
     // StyleAdjuster has ensured that zIndex is non-auto only if it's applicable.
     if (m_box->zIndex() != other.m_box->zIndex() || m_box->hasAutoZIndex() != other.m_box->hasAutoZIndex())
         diff.setZIndexChanged();
 
     if (rareNonInheritedData.get() != other.rareNonInheritedData.get()) {
         if (!transformDataEquivalent(other))
             diff.setTransformChanged();
 
@@ skipping 743 matching lines @@
     // right
     radiiSum = radii.topRight().height() + radii.bottomRight().height();
     if (radiiSum > rect.height())
         factor = std::min(rect.height() / radiiSum, factor);
 
     ASSERT(factor <= 1);
     return factor;
 }
 
 } // namespace blink