Update matrix distance metric to account for snapping.

ui/gfx/transform_util.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/transform_util.h"
 
 #include <algorithm>
 #include <cmath>
 #include <string>
 
@@ skipping 497 matching lines @@
       perspective[0],
       perspective[1],
       perspective[2],
       perspective[3],
       quaternion[0],
       quaternion[1],
       quaternion[2],
       quaternion[3]);
 }
 
-float MatrixDistance(const Transform& a, const Transform& b) {
-  double sum = 0.0;
-
-  const SkMatrix44& a_data = a.matrix();
-  const SkMatrix44& b_data = b.matrix();
-
-  for (int row = 0; row < 4; ++row) {
-    for (int col = 0; col < 4; ++col) {
-      double diff = a_data.get(row, col) - b_data.get(row, col);
-      sum += diff * diff;
-    }
-  }
-
-  return static_cast<float>(std::sqrt(sum));
-}
-
 }  // namespace gfx