Migrate WTF::HashMap::get() to ::at()

third_party/WebKit/Source/core/layout/compositing/CompositedLayerMapping.cpp

 /*
  * Copyright (C) 2009, 2010, 2011 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 289 matching lines @@
     if (!ancestorOverflowLayer->isRootLayer()) {
       sticky = ancestorOverflowLayer->needsCompositedScrolling();
     } else {
       sticky = layoutObject().view()->frameView()->isScrollable();
     }
   }
 
   WebLayerStickyPositionConstraint webConstraint;
   if (sticky) {
     const StickyPositionScrollingConstraints& constraints =
-        ancestorOverflowLayer->getScrollableArea()->stickyConstraintsMap().get(
+        ancestorOverflowLayer->getScrollableArea()->stickyConstraintsMap().at(
             &m_owningLayer);
 
     // Find the layout offset of the unshifted sticky box within its enclosing
     // layer.
     LayoutPoint enclosingLayerOffset;
     m_owningLayer.enclosingLayerWithCompositedLayerMapping(ExcludeSelf)
         ->convertToLayerCoords(m_owningLayer.ancestorOverflowLayer(),
                                enclosingLayerOffset);
     FloatPoint stickyBoxOffset =
         constraints.scrollContainerRelativeStickyBoxRect().location();
@@ skipping 3159 matching lines @@
   } else if (graphicsLayer == m_decorationOutlineLayer.get()) {
     name = "Decoration Layer";
   } else {
     ASSERT_NOT_REACHED();
   }
 
   return name;
 }
 
 }  // namespace blink