cc: Make sure mask and replica layers get DidBecomeActive signal.

cc/test/fake_picture_layer_impl.h

Index: cc/test/fake_picture_layer_impl.h
diff --git a/cc/test/fake_picture_layer_impl.h b/cc/test/fake_picture_layer_impl.h
index f101b0f3e2660f7de72d3726d20ff94f007ff420..ab0c023654ff4c21f1509e89365b1bfae2164a71 100644
--- a/cc/test/fake_picture_layer_impl.h
+++ b/cc/test/fake_picture_layer_impl.h
@@ -41,6 +41,11 @@ class FakePictureLayerImpl : public PictureLayerImpl {
   virtual gfx::Size CalculateTileSize(
       const gfx::Size& content_bounds) const OVERRIDE;
 
+  virtual void DidBecomeActive() OVERRIDE;
+  size_t did_become_active_call_count() {
+    return did_become_active_call_count_;
+  }
+
   using PictureLayerImpl::AddTiling;
   using PictureLayerImpl::CleanUpTilingsOnActiveLayer;
   using PictureLayerImpl::CanHaveTilings;
@@ -110,6 +115,7 @@ class FakePictureLayerImpl : public PictureLayerImpl {
   gfx::Size fixed_tile_size_;
 
   size_t append_quads_count_;
+  size_t did_become_active_call_count_;
 };
 
 }  // namespace cc