x11: Prefer using ui::GetXDisplay() over getting the Display from the X11 message-pump.

ui/aura/root_window_host_x11.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_host_x11.h"
 
 #include <strings.h>
 #include <X11/cursorfont.h>
 #include <X11/extensions/Xfixes.h>
 #include <X11/extensions/XInput2.h>
@@ skipping 345 matching lines @@
   size_t insert_index_;
 
   DISALLOW_COPY_AND_ASSIGN(MouseMoveFilter);
 };
 
 ////////////////////////////////////////////////////////////////////////////////
 // RootWindowHostX11
 
 RootWindowHostX11::RootWindowHostX11(const gfx::Rect& bounds)
     : delegate_(NULL),
-      xdisplay_(base::MessagePumpX11::GetDefaultXDisplay()),
+      xdisplay_(ui::GetXDisplay()),
       xwindow_(0),
       x_root_window_(DefaultRootWindow(xdisplay_)),
       current_cursor_(ui::kCursorNull),
       window_mapped_(false),
       bounds_(bounds),
       is_internal_display_(false),
       focus_when_shown_(false),
       touch_calibrate_(new internal::TouchEventCalibrate),
       mouse_move_filter_(new MouseMoveFilter),
       atom_cache_(xdisplay_, kAtomsToCache),
@@ skipping 706 matching lines @@
 #endif
 }
 
 // static
 RootWindowHost* RootWindowHost::Create(const gfx::Rect& bounds) {
   return new RootWindowHostX11(bounds);
 }
 
 // static
 gfx::Size RootWindowHost::GetNativeScreenSize() {
-  ::Display* xdisplay = base::MessagePumpX11::GetDefaultXDisplay();
+  ::Display* xdisplay = ui::GetXDisplay();
   return gfx::Size(DisplayWidth(xdisplay, 0), DisplayHeight(xdisplay, 0));
 }
 
 namespace test {
 
 void SetUseOverrideRedirectWindowByDefault(bool override_redirect) {
   default_override_redirect = override_redirect;
 }
 
 }  // namespace test
 }  // namespace aura