Add wrapper container for a vector of OwnPtr<T>

cc/CCLayerTreeHostCommon.cpp

 // Copyright 2011 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 
 #include "config.h"
 
 #include "CCLayerTreeHostCommon.h"
 
 #include "CCLayerImpl.h"
@@ skipping 617 matching lines @@
     // Any layers that are appended after this point are in the layer's subtree and should be included in the sorting process.
     unsigned sortingStartIndex = descendants.size();
 
     if (!layerShouldBeSkipped(layer))
         descendants.append(layer);
 
     WebTransformationMatrix nextScrollCompensationMatrix = computeScrollCompensationMatrixForChildren(layer, parentMatrix, currentScrollCompensationMatrix);;
 
     IntRect accumulatedDrawableContentRectOfChildren;
     for (size_t i = 0; i < layer->children().size(); ++i) {
-        LayerType* child = layer->children()[i].get();
+        LayerType* child = CCLayerTreeHostCommon::getChildAsRawPtr(layer->children(), i);
         IntRect drawableContentRectOfChildSubtree;
         calculateDrawTransformsInternal<LayerType, LayerList, RenderSurfaceType, LayerSorter>(child, rootLayer, sublayerMatrix, nextHierarchyMatrix, nextScrollCompensationMatrix,
                                                                                               clipRectForSubtree, subtreeShouldBeClipped, nearestAncestorThatMovesPixels,
                                                                                               renderSurfaceLayerList, descendants, layerSorter, maxTextureSize, deviceScaleFactor, drawableContentRectOfChildSubtree);
         if (!drawableContentRectOfChildSubtree.isEmpty()) {
             accumulatedDrawableContentRectOfChildren.unite(drawableContentRectOfChildSubtree);
             if (child->renderSurface())
                 descendants.append(child);
         }
     }
@@ skipping 227 matching lines @@
 
         foundLayer = currentLayer;
         break;
     }
 
     // This can potentially return 0, which means the viewportPoint did not successfully hit test any layers, not even the root layer.
     return foundLayer;
 }
 
 } // namespace cc