Make all LayerAnimationElement::Create*Element return unique_ptr

ui/compositor/layer_unittest.cc

 // 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.
 
 #include "ui/compositor/layer.h"
 
 #include <stddef.h>
 
 #include <memory>
 #include <utility>
@@ skipping 2144 matching lines @@
   std::unique_ptr<Layer> child(CreateLayer(LAYER_TEXTURED));
   root->Add(parent.get());
   parent->Add(child.get());
   compositor()->SetRootLayer(root.get());
 
   child->SetAnimator(LayerAnimator::CreateDefaultAnimator());
 
   LayerRemovingLayerAnimationObserver observer(root.get(), parent.get());
   child->GetAnimator()->AddObserver(&observer);
 
-  LayerAnimationElement* element =
+  std::unique_ptr<LayerAnimationElement> element =
       ui::LayerAnimationElement::CreateOpacityElement(
           0.5f, base::TimeDelta::FromSeconds(1));
-  LayerAnimationSequence* sequence = new LayerAnimationSequence(element);
+  LayerAnimationSequence* sequence =
+      new LayerAnimationSequence(std::move(element));
 
   child->GetAnimator()->StartAnimation(sequence);
   EXPECT_TRUE(compositor()->layer_animator_collection()->HasActiveAnimators());
 
   child->GetAnimator()->StopAnimating();
   EXPECT_FALSE(root->Contains(parent.get()));
   EXPECT_FALSE(compositor()->layer_animator_collection()->HasActiveAnimators());
 }
 
 namespace {
@@ skipping 97 matching lines @@
   layer.set_name("foo");
   std::unique_ptr<base::trace_event::ConvertableToTraceFormat> debug_info =
       layer.TakeDebugInfo(nullptr);
   std::string trace_format("bar,");
   debug_info->AppendAsTraceFormat(&trace_format);
   std::string expected("bar,{\"layer_name\":\"foo\"}");
   EXPECT_EQ(expected, trace_format);
 }
 
 }  // namespace ui