Refactor TransformPoint{,Reverse}.

ui/aura/root_window.cc

Index: ui/aura/root_window.cc
diff --git a/ui/aura/root_window.cc b/ui/aura/root_window.cc
index 0c7253be85f9a79e1f7614f6b48c4485f36cf8cc..df8b6722d8f1bc5be7c0946d4d9d091a176f3790 100644
--- a/ui/aura/root_window.cc
+++ b/ui/aura/root_window.cc
@@ -445,13 +445,13 @@ void RootWindow::ConvertPointFromNativeScreen(gfx::Point* point) const {
 
 void RootWindow::ConvertPointToHost(gfx::Point* point) const {
   gfx::Point3F point_3f(*point);
-  GetRootTransform().TransformPoint(point_3f);
+  GetRootTransform().TransformPoint(&point_3f);
   *point = gfx::ToFlooredPoint(point_3f.AsPointF());
 }
 
 void RootWindow::ConvertPointFromHost(gfx::Point* point) const {
   gfx::Point3F point_3f(*point);
-  GetInverseRootTransform().TransformPoint(point_3f);
+  GetInverseRootTransform().TransformPoint(&point_3f);
   *point = gfx::ToFlooredPoint(point_3f.AsPointF());
 }