cc: Add readback and forced draw states to the Scheduler

cc/test/layer_tree_test.h

Index: cc/test/layer_tree_test.h
diff --git a/cc/test/layer_tree_test.h b/cc/test/layer_tree_test.h
index c6a3f4dc75e2f9ed35b9b4de3bcbf5a59d6a5074..5ac3f8558eb1da14d876e221e78083709af4b662 100644
--- a/cc/test/layer_tree_test.h
+++ b/cc/test/layer_tree_test.h
@@ -112,6 +112,7 @@ class LayerTreeTest : public testing::Test, public TestHooks {
   void PostAddAnimationToMainThread(Layer* layer_to_receive_animation);
   void PostAddInstantAnimationToMainThread(Layer* layer_to_receive_animation);
   void PostSetNeedsCommitToMainThread();
+  void PostReadbackToMainThread();
   void PostAcquireLayerTextures();
   void PostSetNeedsRedrawToMainThread();
   void PostSetNeedsRedrawRectToMainThread(gfx::Rect damage_rect);
@@ -132,6 +133,7 @@ class LayerTreeTest : public testing::Test, public TestHooks {
   virtual void DispatchAddInstantAnimation(Layer* layer_to_receive_animation);
   virtual void DispatchAddAnimation(Layer* layer_to_receive_animation);
   void DispatchSetNeedsCommit();
+  void DispatchReadback();
   void DispatchAcquireLayerTextures();
   void DispatchSetNeedsRedraw();
   void DispatchSetNeedsRedrawRect(gfx::Rect damage_rect);