ui: Prefer +/- operators to apply offsets.

cc/math_util.cc

Index: cc/math_util.cc
diff --git a/cc/math_util.cc b/cc/math_util.cc
index f18b840146025accc4bbf8541eafcbc38dcf641a..4714ae77e0554a1a26488d9f5fb8c8334def934f 100644
--- a/cc/math_util.cc
+++ b/cc/math_util.cc
@@ -110,11 +110,8 @@ gfx::Rect MathUtil::mapClippedRect(const WebTransformationMatrix& transform, con
 
 gfx::RectF MathUtil::mapClippedRect(const WebTransformationMatrix& transform, const gfx::RectF& srcRect)
 {
-    if (transform.isIdentityOrTranslation()) {
-        gfx::RectF mappedRect(srcRect);
-        mappedRect.Offset(static_cast<float>(transform.m41()), static_cast<float>(transform.m42()));
-        return mappedRect;
-    }
+    if (transform.isIdentityOrTranslation())
+        return srcRect + gfx::Vector2dF(static_cast<float>(transform.m41()), static_cast<float>(transform.m42()));
 
     // Apply the transform, but retain the result in homogeneous coordinates.
     gfx::QuadF q = gfx::QuadF(gfx::RectF(srcRect));