Migrate from MathUtil::inverse() to gfx::Transform::GetInverse()

cc/test/geometry_test_utils.cc

 // Copyright 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 "cc/test/geometry_test_utils.h"
 
+#include "base/logging.h"
 #include "testing/gtest/include/gtest/gtest.h"
 #include "third_party/WebKit/Source/Platform/chromium/public/WebTransformationMatrix.h"
 #include "ui/gfx/transform.h"
 
 namespace cc {
 
 // NOTE: even though transform data types use double precision, we only check
 // for equality within single-precision error bounds because many transforms
 // originate from single-precision data types such as quads/rects/etc.
 
@@ skipping 32 matching lines @@
     EXPECT_FLOAT_EQ((expected).matrix().getDouble(0, 2), (actual).matrix().getDouble(0, 2));
     EXPECT_FLOAT_EQ((expected).matrix().getDouble(1, 2), (actual).matrix().getDouble(1, 2));
     EXPECT_FLOAT_EQ((expected).matrix().getDouble(2, 2), (actual).matrix().getDouble(2, 2));
     EXPECT_FLOAT_EQ((expected).matrix().getDouble(3, 2), (actual).matrix().getDouble(3, 2));
     EXPECT_FLOAT_EQ((expected).matrix().getDouble(0, 3), (actual).matrix().getDouble(0, 3));
     EXPECT_FLOAT_EQ((expected).matrix().getDouble(1, 3), (actual).matrix().getDouble(1, 3));
     EXPECT_FLOAT_EQ((expected).matrix().getDouble(2, 3), (actual).matrix().getDouble(2, 3));
     EXPECT_FLOAT_EQ((expected).matrix().getDouble(3, 3), (actual).matrix().getDouble(3, 3));
 }
 
+gfx::Transform inverse(const gfx::Transform& transform)
+{
+    gfx::Transform result;

[danakj, 2013/01/04 21:56:07]

SkipInitialization?

+    bool invertedSuccessfully = transform.GetInverse(&result);
+    DCHECK(invertedSuccessfully);
+    return result;
+}
+
 }  // namespace cc