Reenable synthesized mouse event on win aura

ui/aura/root_window.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/aura/root_window.h"
 
 #include <vector>
 
 #include "base/auto_reset.h"
 #include "base/bind.h"
@@ skipping 974 matching lines @@
   MessageLoop::current()->PostTask(
       FROM_HERE,
       base::Bind(&RootWindow::SynthesizeMouseMoveEvent,
                  event_factory_.GetWeakPtr()));
 }
 
 void RootWindow::SynthesizeMouseMoveEvent() {
   if (!synthesize_mouse_move_)
     return;
   synthesize_mouse_move_ = false;
-#if !defined(OS_WIN)
-  // Temporarily disabled for windows. See crbug.com/112222.
   gfx::Point3F point(GetLastMouseLocationInRoot());
   float scale = ui::GetDeviceScaleFactor(layer());
   gfx::Transform transform;
   transform.Scale(scale, scale);
   transform *= layer()->transform();
   transform.TransformPoint(point);
   gfx::Point orig_mouse_location = gfx::ToFlooredPoint(point.AsPointF());
 
   // TODO(derat|oshima): Don't use mouse_button_flags_ as it's
   // currently broken. See/ crbug.com/107931.
   ui::MouseEvent event(ui::ET_MOUSE_MOVED,
                        orig_mouse_location,
                        orig_mouse_location,
                        ui::EF_IS_SYNTHESIZED);
   event.set_system_location(Env::GetInstance()->last_mouse_location());
   OnHostMouseEvent(&event);
-#endif
 }
 
 }  // namespace aura