Update from https://crrev.com/309415

ui/gfx/transform.h

Index: ui/gfx/transform.h
diff --git a/ui/gfx/transform.h b/ui/gfx/transform.h
index 6028fb37b4328ff677e05669bc331819c65e4947..8156b7265c936004178dbfd74f8fea36af7d83f0 100644
--- a/ui/gfx/transform.h
+++ b/ui/gfx/transform.h
@@ -122,6 +122,11 @@ class GFX_EXPORT Transform {
   // 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;