Remove unneeded ScopedLayerAnimationSettings::LockTransitionDuration()

ui/compositor/scoped_layer_animation_settings.h

 // Copyright (c) 2012 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 UI_COMPOSITOR_SCOPED_LAYER_ANIMATION_SETTINGS_H_
 #define UI_COMPOSITOR_SCOPED_LAYER_ANIMATION_SETTINGS_H_
 
 #include <set>
 
 #include "base/memory/scoped_vector.h"
@@ skipping 16 matching lines @@
 class COMPOSITOR_EXPORT ScopedLayerAnimationSettings {
  public:
   explicit ScopedLayerAnimationSettings(LayerAnimator* animator);
   virtual ~ScopedLayerAnimationSettings();
 
   void AddObserver(ImplicitAnimationObserver* observer);
 
   void SetTransitionDuration(base::TimeDelta duration);
   base::TimeDelta GetTransitionDuration() const;
 
-  // Locks transition duration in |animator_|. When transition duration
-  // is locked any subsequent changes to it are ignored until the
-  // ScopedLayerAnimationSettings object that has locked the duration goes out
-  // of scope.
-  void LockTransitionDuration();
-
   void SetTweenType(gfx::Tween::Type tween_type);
   gfx::Tween::Type GetTweenType() const;
 
   void SetPreemptionStrategy(LayerAnimator::PreemptionStrategy strategy);
   LayerAnimator::PreemptionStrategy GetPreemptionStrategy() const;
 
   // Sets the base layer whose animation will be countered.
   void SetInverselyAnimatedBaseLayer(Layer* base);
 
   // Adds the layer to be counter-animated when a transform animation is
   // scheduled on the animator_. Must call SetInverselyAnimatedBaseLayer with
   // the layer associated with animator_ before animating.
   void AddInverselyAnimatedLayer(Layer* inverse_layer);
 
  private:
   LayerAnimator* animator_;
-  bool old_is_transition_duration_locked_;
   base::TimeDelta old_transition_duration_;
   gfx::Tween::Type old_tween_type_;
   LayerAnimator::PreemptionStrategy old_preemption_strategy_;
   std::set<ImplicitAnimationObserver*> observers_;
   scoped_ptr<InvertingObserver> inverse_observer_;
 
   DISALLOW_COPY_AND_ASSIGN(ScopedLayerAnimationSettings);
 };
 
 }  // namespace ui
 
 #endif  // UI_COMPOSITOR_SCOPED_LAYER_ANIMATION_SETTINGS_H_