cc: Switch RenderingStats collection in Layer::Update() to RenderingStatsInstrumentation

cc/layers/layer.cc

Index: cc/layers/layer.cc
diff --git a/cc/layers/layer.cc b/cc/layers/layer.cc
index e72e7b1b87dbf881e5627b75ad4e2196bc5586f8..66348493fcb9ec6e410ce06bbed61750aefb346d 100644
--- a/cc/layers/layer.cc
+++ b/cc/layers/layer.cc
@@ -817,4 +817,9 @@ ScrollbarLayer* Layer::ToScrollbarLayer() {
   return NULL;
 }
 
+RenderingStatsInstrumentation* Layer::rendering_stats_instrumentation() const {
+  CHECK(layer_tree_host());

[danakj, 2013/03/26 18:47:50]

The check is kind of redundant. We'll crash on the layer_tree_host() NULL deref
anyways. And a null deref isn't accessing arbitrary memory, so I don't think you
need the CHECK() here.

+  return layer_tree_host()->rendering_stats_instrumentation();

[danakj, 2013/03/26 18:47:50]

nit: layer_tree_host_->

+}
+
 }  // namespace cc