WIP - compositor worker mega patch.

cc/trees/layer_tree_host_client.h

Index: cc/trees/layer_tree_host_client.h
diff --git a/cc/trees/layer_tree_host_client.h b/cc/trees/layer_tree_host_client.h
index e37d8e02600cc6ca90e653ac6215aeafe3031bf1..2da49a3c76a2d206502c366e1bb1361f1e38d797 100644
--- a/cc/trees/layer_tree_host_client.h
+++ b/cc/trees/layer_tree_host_client.h
@@ -8,6 +8,7 @@
 #include "base/memory/ref_counted.h"
 #include "base/memory/scoped_ptr.h"
 #include "base/time/time.h"
+#include "cc/animation/layer_tree_mutation.h"
 #include "cc/debug/frame_timing_tracker.h"
 
 namespace gfx {
@@ -47,6 +48,7 @@ class LayerTreeHostClient {
       const gfx::Vector2dF& elastic_overscroll_delta,
       float page_scale,
       float top_controls_delta) = 0;
+  virtual void ApplyMutations(const LayerTreeMutationMap& mutations) = 0;
   // Request an OutputSurface from the client. When the client has one it should
   // call LayerTreeHost::SetOutputSurface.  This will result in either
   // DidFailToInitializeOutputSurface or DidInitializeOutputSurface being