Update from https://crrev.com/309415

ui/gfx/transform.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_GFX_TRANSFORM_H_
 #define UI_GFX_TRANSFORM_H_
 
 #include <iosfwd>
 #include <string>
 
@@ skipping 104 matching lines @@
   // Applies a transformation on the current transformation
   // (i.e. 'this = transform * this;').
   void ConcatTransform(const Transform& transform);
 
   // Returns true if this is the identity matrix.
   bool IsIdentity() const { return matrix_.isIdentity(); }
 
   // Returns true if the matrix is either identity or pure translation.
   bool IsIdentityOrTranslation() const { return matrix_.isTranslate(); }
 
+  // Returns true if the matrix is either the identity or a 2d translation.
+  bool IsIdentityOr2DTranslation() const {
+    return matrix_.isTranslate() && matrix_.get(2, 3) == 0;
+  }
+
   // Returns true if the matrix is either identity or pure translation,
   // allowing for an amount of inaccuracy as specified by the parameter.
   bool IsApproximatelyIdentityOrTranslation(SkMScalar tolerance) const;
 
   // Returns true if the matrix is either a positive scale and/or a translation.
   bool IsPositiveScaleOrTranslation() const {
     if (!IsScaleOrTranslation())
       return false;
     return matrix_.get(0, 0) > 0.0 && matrix_.get(1, 1) > 0.0 &&
            matrix_.get(2, 2) > 0.0;
@@ skipping 128 matching lines @@
 };
 
 // This is declared here for use in gtest-based unit tests but is defined in
 // the gfx_test_support target. Depend on that to use this in your unit test.
 // This should not be used in production code - call ToString() instead.
 void PrintTo(const Transform& transform, ::std::ostream* os);
 
 }  // namespace gfx
 
 #endif  // UI_GFX_TRANSFORM_H_