cc: Allow sending BeginMainFrame before draw or activation

cc/scheduler/scheduler_state_machine.h

 // Copyright 2011 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef CC_SCHEDULER_SCHEDULER_STATE_MACHINE_H_
 #define CC_SCHEDULER_SCHEDULER_STATE_MACHINE_H_
 
 #include <string>
 
 #include "base/basictypes.h"
@@ skipping 43 matching lines @@
     BEGIN_FRAME_STATE_INSIDE_BEGIN_FRAME,
     BEGIN_FRAME_STATE_DEADLINE_PENDING,
     BEGIN_FRAME_STATE_INSIDE_DEADLINE,
   };
   static const char* BeginFrameStateToString(BeginFrameState state);
 
   enum CommitState {
     COMMIT_STATE_IDLE,
     COMMIT_STATE_FRAME_IN_PROGRESS,
     COMMIT_STATE_READY_TO_COMMIT,
-    COMMIT_STATE_WAITING_FOR_FIRST_DRAW,
   };
   static const char* CommitStateToString(CommitState state);
 
   enum TextureState {
     LAYER_TEXTURE_STATE_UNLOCKED,
     LAYER_TEXTURE_STATE_ACQUIRED_BY_MAIN_THREAD,
     LAYER_TEXTURE_STATE_ACQUIRED_BY_IMPL_THREAD,
   };
   static const char* TextureStateToString(TextureState state);
 
@@ skipping 110 matching lines @@
 
   // Indicates whether drawing would, at this time, make sense.
   // CanDraw can be used to supress flashes or checkerboarding
   // when such behavior would be undesirable.
   void SetCanDraw(bool can);
 
   // Indicates that the pending tree is ready for activation.
   void NotifyReadyToActivate();
 
   bool has_pending_tree() const { return has_pending_tree_; }
+  bool active_tree_needs_first_draw() const {
+    return active_tree_needs_first_draw_;
+  }
 
   void DidLoseOutputSurface();
   void DidCreateAndInitializeOutputSurface();
   bool HasInitializedOutputSurface() const;
 
   // True if we need to abort draws to make forward progress.
   bool PendingDrawsShouldBeAborted() const;
 
  protected:
   // True if we need to force activations to make forward progress.
@@ skipping 53 matching lines @@
   bool draw_if_possible_failed_;
   bool did_create_and_initialize_first_output_surface_;
 
  private:
   DISALLOW_COPY_AND_ASSIGN(SchedulerStateMachine);
 };
 
 }  // namespace cc
 
 #endif  // CC_SCHEDULER_SCHEDULER_STATE_MACHINE_H_