Migrate ui::Transform to gfx::Transform

ui/compositor/test/test_utils.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_TEST_TEST_UTILS_H_
 #define UI_COMPOSITOR_TEST_TEST_UTILS_H_
 
 namespace gfx {
 class Rect;
+class Transform;
 }
 
 namespace ui {
 
-class Transform;
-
-void CheckApproximatelyEqual(const Transform& lhs, const Transform& rhs);
+void CheckApproximatelyEqual(const gfx::Transform& lhs,
+                             const gfx::Transform& rhs);
 void CheckApproximatelyEqual(const gfx::Rect& lhs, const gfx::Rect& rhs);
 
 }  // namespace ui
 
 #endif  // UI_COMPOSITOR_TEST_TEST_UTILS_H_