Support creation of toplevel mus::Windows on separate displays

ash/mus/bridge/wm_window_mus.cc

Index: ash/mus/bridge/wm_window_mus.cc
diff --git a/ash/mus/bridge/wm_window_mus.cc b/ash/mus/bridge/wm_window_mus.cc
index d327bc70be53b11be3624374275fd2cfe5d39c04..c77d976757dc73631330f53dc0350914ef1bcdc1 100644
--- a/ash/mus/bridge/wm_window_mus.cc
+++ b/ash/mus/bridge/wm_window_mus.cc
@@ -133,7 +133,6 @@ WmWindowMus::~WmWindowMus() {
 const WmWindowMus* WmWindowMus::Get(const ui::Window* window) {
   if (!window)
     return nullptr;
-

[mfomitchev, 2016/11/17 17:14:01]

Doesn't seem like there's particular reason to remove this line (especially
considering this is the only change to the file).

[thanhph, 2016/11/17 19:08:30]

Done.

   const WmWindowMus* wm_window = window->GetLocalProperty(kWmWindowKey);
   if (wm_window)
     return wm_window;