Remove unneeded ScopedLayerAnimationSettings::LockTransitionDuration()

ui/compositor/scoped_layer_animation_settings.cc

Index: ui/compositor/scoped_layer_animation_settings.cc
diff --git a/ui/compositor/scoped_layer_animation_settings.cc b/ui/compositor/scoped_layer_animation_settings.cc
index 84456ee5bc16c3268aae4bf593770c4b425eeddc..4ae42ea93cbb50a5ae5cb6140f314ada66bd4858 100644
--- a/ui/compositor/scoped_layer_animation_settings.cc
+++ b/ui/compositor/scoped_layer_animation_settings.cc
@@ -81,9 +81,7 @@ class InvertingObserver : public ImplicitAnimationObserver {
 ScopedLayerAnimationSettings::ScopedLayerAnimationSettings(
     LayerAnimator* animator)
     : animator_(animator),
-      old_is_transition_duration_locked_(
-          animator->is_transition_duration_locked_),
-      old_transition_duration_(animator->GetTransitionDuration()),
+      old_transition_duration_(animator->transition_duration_),
       old_tween_type_(animator->tween_type()),
       old_preemption_strategy_(animator->preemption_strategy()),
       inverse_observer_(new InvertingObserver()) {
@@ -92,9 +90,7 @@ ScopedLayerAnimationSettings::ScopedLayerAnimationSettings(
 }
 
 ScopedLayerAnimationSettings::~ScopedLayerAnimationSettings() {
-  animator_->is_transition_duration_locked_ =
-      old_is_transition_duration_locked_;
-  animator_->SetTransitionDuration(old_transition_duration_);
+  animator_->transition_duration_ = old_transition_duration_;
   animator_->set_tween_type(old_tween_type_);
   animator_->set_preemption_strategy(old_preemption_strategy_);
 
@@ -117,11 +113,7 @@ void ScopedLayerAnimationSettings::AddObserver(
 
 void ScopedLayerAnimationSettings::SetTransitionDuration(
     base::TimeDelta duration) {
-  animator_->SetTransitionDuration(duration);
-}
-
-void ScopedLayerAnimationSettings::LockTransitionDuration() {
-  animator_->is_transition_duration_locked_ = true;
+  animator_->transition_duration_ = duration;
 }
 
 base::TimeDelta ScopedLayerAnimationSettings::GetTransitionDuration() const {