compositor/layer_animator: handle delegate removal in LayerAnimation::StopAnimating

ui/compositor/layer_animator_unittest.cc

Index: ui/compositor/layer_animator_unittest.cc
diff --git a/ui/compositor/layer_animator_unittest.cc b/ui/compositor/layer_animator_unittest.cc
index 99d2426c0299fc6bf3c110c48729aa7ae06aa36e..5f2823cdd1358a75fd9b31368e1fcb5ee9781cd3 100644
--- a/ui/compositor/layer_animator_unittest.cc
+++ b/ui/compositor/layer_animator_unittest.cc
@@ -2611,4 +2611,69 @@ TEST(LayerAnimatorTest, LayerMovedBetweenCompositorsDuringAnimation) {
   TerminateContextFactoryForTests();
 }
 
+class LayerOwnerAnimationObserver : public LayerAnimationObserver {
+ public:
+  LayerOwnerAnimationObserver(LayerAnimator* animator)
+      : animator_layer_(new Layer(LAYER_TEXTURED)) {
+    animator_layer_->SetAnimator(animator);
+  }
+
+  virtual ~LayerOwnerAnimationObserver() {}

[sky, 2015/01/05 17:54:52]

no virtual, just override.

+
+  void OnLayerAnimationEnded(LayerAnimationSequence* sequence) override {
+    ASSERT_TRUE(sequence);
+    reset_layer();
+  }
+
+  void OnLayerAnimationAborted(LayerAnimationSequence* sequence) override {
+    ASSERT_TRUE(sequence);
+    reset_layer();
+  }
+
+  LayerAnimationDelegate* get_animator_delegate() {

[sky, 2015/01/05 17:54:52]

Style guide says this should be named animator_layer() (match the field name).

+    return animator_layer_.get();
+  }
+
+  void OnLayerAnimationScheduled(LayerAnimationSequence* sequence) override {}
+
+ private:
+  void reset_layer() { animator_layer_.reset(); }

[sky, 2015/01/05 17:54:52]

This function is a single liner and doesn't add any value. Make the call sites
call animator_layer_.reset() and nuke the function.

+
+  scoped_ptr<Layer> animator_layer_;
+
+  DISALLOW_COPY_AND_ASSIGN(LayerOwnerAnimationObserver);
+};
+
+TEST(LayerAnimatorTest, ObserverRemovesLayerInStopAnimating) {

[sky, 2015/01/05 17:54:52]

Removes->Deletes.

+  scoped_refptr<LayerAnimator> animator(
+      LayerAnimator::CreateImplicitAnimator());
+  animator->set_disable_timer_for_test(true);
+  LayerOwnerAnimationObserver observer(animator.get());
+  LayerAnimationDelegate* delegate = observer.get_animator_delegate();
+
+  const gfx::Rect start_bounds(0, 0, 50, 50);
+  const gfx::Rect target_bounds(10, 10, 100, 100);
+  const double target_opacity = 1.0;
+
+  delegate->SetOpacityFromAnimation(0.0f);
+  delegate->SetBoundsFromAnimation(start_bounds);
+
+  base::TimeDelta time_delta = base::TimeDelta::FromSeconds(1);
+  LayerAnimationSequence* opacity = new LayerAnimationSequence(
+      LayerAnimationElement::CreateOpacityElement(target_opacity, time_delta));
+  opacity->AddObserver(&observer);
+  animator->ScheduleAnimation(opacity);
+  time_delta = base::TimeDelta::FromSeconds(2);
+  LayerAnimationSequence* move = new LayerAnimationSequence(
+      LayerAnimationElement::CreateBoundsElement(target_bounds, time_delta));
+  animator->ScheduleAnimation(move);
+  EXPECT_TRUE(animator->is_animating());
+  animator->Step(animator->last_step_time() +
+                 base::TimeDelta::FromMilliseconds(500));
+  animator->StopAnimating();
+
+  EXPECT_EQ(observer.get_animator_delegate(), nullptr);

[sky, 2015/01/05 17:54:52]

assertions have the format expected, actual. nullptr should be first.

+  EXPECT_TRUE(animator->is_animating());
+}
+
 }  // namespace ui