cc: Block commit on activate by setting a flag on LayerTreeHost.

cc/trees/layer_tree_host.cc

Index: cc/trees/layer_tree_host.cc
diff --git a/cc/trees/layer_tree_host.cc b/cc/trees/layer_tree_host.cc
index f18e3b865409bd20d0c17468d03396cca14c09b0..9e6b5ef6f513634e74231f8499d1e1760779472d 100644
--- a/cc/trees/layer_tree_host.cc
+++ b/cc/trees/layer_tree_host.cc
@@ -88,6 +88,7 @@ LayerTreeHost::LayerTreeHost(LayerTreeHostClient* client,
       animating_(false),
       needs_full_tree_sync_(true),
       needs_filter_context_(false),
+      commit_waits_for_activation_(false),
       client_(client),
       source_frame_number_(0),
       rendering_stats_instrumentation_(RenderingStatsInstrumentation::Create()),
@@ -383,6 +384,7 @@ void LayerTreeHost::FinishCommitOnImplThread(LayerTreeHostImpl* host_impl) {
     sync_tree->DidBecomeActive();
   }
 
+  commit_waits_for_activation_ = false;
   source_frame_number_++;
 }
 
@@ -1089,12 +1091,6 @@ void LayerTreeHost::UpdateTopControlsState(TopControlsState constraints,
                  animate));
 }
 
-bool LayerTreeHost::BlocksPendingCommit() const {
-  if (!root_layer_.get())
-    return false;
-  return root_layer_->BlocksPendingCommitRecursive();
-}
-
 scoped_ptr<base::Value> LayerTreeHost::AsValue() const {
   scoped_ptr<base::DictionaryValue> state(new base::DictionaryValue());
   state->Set("proxy", proxy_->AsValue().release());