cc: Avoid deadlock with the UI thread and NPAPI in more cases

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 250 matching lines @@
   bool BeginFrameRequiredForAction() const;
   bool BeginFrameRequiredForChildren() const;
   bool BeginFrameNeededForVideo() const;
   bool ProactiveBeginFrameWanted() const;
 
   bool ShouldTriggerBeginImplFrameDeadlineImmediately() const;
 
   // True if we need to force activations to make forward progress.
   bool PendingActivationsShouldBeForced() const;
 
+  // TODO(brianderson): Remove this once NPAPI support is removed.
+  bool SendingBeginMainFrameMightCauseDeadlock() const;
+
   bool ShouldAnimate() const;
   bool ShouldBeginOutputSurfaceCreation() const;
   bool ShouldDraw() const;
   bool ShouldActivatePendingTree() const;
   bool ShouldSendBeginMainFrame() const;
   bool ShouldCommit() const;
   bool ShouldPrepareTiles() const;
   bool ShouldInvalidateOutputSurface() const;
 
   void UpdateStateOnAnimate();
@@ skipping 59 matching lines @@
   bool did_request_swap_in_last_frame_;
   bool did_perform_swap_in_last_draw_;
 
  private:
   DISALLOW_COPY_AND_ASSIGN(SchedulerStateMachine);
 };
 
 }  // namespace cc
 
 #endif  // CC_SCHEDULER_SCHEDULER_STATE_MACHINE_H_