Pass the ImageSkia by pointer instead of by reference, which will create shallow copy.

ui/gfx/image/image_skia_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/gfx/image/image_skia.h"
 
 #include "base/logging.h"
 #include "base/threading/simple_thread.h"
 #include "testing/gtest/include/gtest/gtest.h"
 #include "third_party/skia/include/core/SkBitmap.h"
@@ skipping 275 matching lines @@
   // so other thread cannot read/modify it.
   image.image_reps();
   test::TestOnThread image_on_thread2(&image);
   image_on_thread2.StartAndJoin();
   EXPECT_FALSE(image_on_thread2.can_read());
   EXPECT_FALSE(image_on_thread2.can_modify());
   EXPECT_TRUE(image.CanRead());
   EXPECT_TRUE(image.CanModify());
 
   image.DetachStorageFromThread();
-  ImageSkia deep_copy = image.DeepCopy();
-  EXPECT_FALSE(deep_copy.IsThreadSafe());
-  test::TestOnThread deepcopy_on_thread(&deep_copy);
+  scoped_ptr<ImageSkia> deep_copy(image.DeepCopy());
+  EXPECT_FALSE(deep_copy->IsThreadSafe());
+  test::TestOnThread deepcopy_on_thread(deep_copy.get());
   deepcopy_on_thread.StartAndJoin();
   EXPECT_TRUE(deepcopy_on_thread.can_read());
   EXPECT_TRUE(deepcopy_on_thread.can_modify());
-  EXPECT_FALSE(deep_copy.CanRead());
-  EXPECT_FALSE(deep_copy.CanModify());
+  EXPECT_FALSE(deep_copy->CanRead());
+  EXPECT_FALSE(deep_copy->CanModify());
 
-  ImageSkia deep_copy2 = image.DeepCopy();
-  EXPECT_EQ(1U, deep_copy2.image_reps().size());
+  scoped_ptr<ImageSkia> deep_copy2(image.DeepCopy());
+  EXPECT_EQ(1U, deep_copy2->image_reps().size());
   // Access it from current thread so that it can't be
   // accessed from another thread.
-  deep_copy2.image_reps();
-  EXPECT_FALSE(deep_copy2.IsThreadSafe());
-  test::TestOnThread deepcopy2_on_thread(&deep_copy2);
+  deep_copy2->image_reps();
+  EXPECT_FALSE(deep_copy2->IsThreadSafe());
+  test::TestOnThread deepcopy2_on_thread(deep_copy2.get());
   deepcopy2_on_thread.StartAndJoin();
   EXPECT_FALSE(deepcopy2_on_thread.can_read());
   EXPECT_FALSE(deepcopy2_on_thread.can_modify());
-  EXPECT_TRUE(deep_copy2.CanRead());
-  EXPECT_TRUE(deep_copy2.CanModify());
+  EXPECT_TRUE(deep_copy2->CanRead());
+  EXPECT_TRUE(deep_copy2->CanModify());
 
   image.DetachStorageFromThread();
   image.SetReadOnly();
   // A read-only ImageSkia with no source is thread safe.
   EXPECT_TRUE(image.IsThreadSafe());
   test::TestOnThread readonly_on_thread(&image);
   readonly_on_thread.StartAndJoin();
   EXPECT_TRUE(readonly_on_thread.can_read());
   EXPECT_FALSE(readonly_on_thread.can_modify());
   EXPECT_TRUE(image.CanRead());
@@ skipping 56 matching lines @@
   EXPECT_FALSE(threadsafe_on_thread.can_modify());
   EXPECT_TRUE(image.CanRead());
   EXPECT_FALSE(image.CanModify());
 }
 #endif  // ENABLE_NON_THREAD_SAFE
 
 // Just in case we ever get lumped together with other compilation units.
 #undef ENABLE_NON_THREAD_SAFE
 
 }  // namespace gfx