Refactor PaintLayer location and offset calculation especially for floats

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

 /*
  * Copyright (C) 2012 Apple Inc. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions
  * are met:
  * 1. Redistributions of source code must retain the above copyright
  *    notice, this list of conditions and the following disclaimer.
  * 2. Redistributions in binary form must reproduce the above copyright
  *    notice, this list of conditions and the following disclaimer in the
@@ skipping 187 matching lines @@
     if (style.position() == FixedPosition || style.isFlippedBlocksWritingMode())
       return false;
 
     if (current->style()->canContainFixedPositionObjects() ||
         current->isLayoutFlowThread() || current->isSVGRoot())
       return false;
 
     if (current == ancestor)
       break;
 
-    if (current->isFloating() && current->parent() &&
-        !current->parent()->isLayoutBlock())
+    if (current->isFloatingWithNonContainingBlockParent())
       return false;
   }
 
   return true;
 }
 
 void LayoutGeometryMap::pushMappingsToAncestor(
     const PaintLayer* layer,
     const PaintLayer* ancestorLayer) {
   const LayoutObject* layoutObject = layer->layoutObject();
@@ skipping 153 matching lines @@
   // If we're not working with multiple LayoutViews, then any view is considered
   // "topmost" (to preserve original behavior).
   if (!(m_mapCoordinatesFlags & TraverseDocumentBoundaries))
     return true;
 
   return layoutObject->frame()->isMainFrame();
 }
 #endif
 
 }  // namespace blink