Cancel drag if display configuration changes.

ui/aura/root_window_host_linux.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_linux.h"
 
 #include <X11/cursorfont.h>
 #include <X11/extensions/Xfixes.h>
 #include <X11/extensions/XInput2.h>
 #include <X11/extensions/Xrandr.h>
@@ skipping 1150 matching lines @@
       break;
   }
   XSendEvent(xdisplay_, xwindow_, False, 0, &xevent);
 }
 
 void RootWindowHostLinux::OnDeviceScaleFactorChanged(
     float device_scale_factor) {
   image_cursors_->Reload(device_scale_factor);
 }
 
+void RootWindowHostLinux::PrepareForShutdown() {
+  base::MessagePumpAuraX11::Current()->RemoveDispatcherForWindow(xwindow_);
+}
+
 bool RootWindowHostLinux::IsWindowManagerPresent() {
   // Per ICCCM 2.8, "Manager Selections", window managers should take ownership
   // of WM_Sn selections (where n is a screen number).
   return XGetSelectionOwner(
       xdisplay_, atom_cache_.GetAtom("WM_S0")) != None;
 }
 
 void RootWindowHostLinux::SetCursorInternal(gfx::NativeCursor cursor) {
   // At times the cursor on the RootWindow is set before it is displayed. So
   // make sure the image-cursors are initialized properly before setting it.
@@ skipping 26 matching lines @@
       ui::ViewProp::GetValue(accelerated_widget, kRootWindowHostLinuxKey));
 }
 
 // static
 gfx::Size RootWindowHost::GetNativeScreenSize() {
   ::Display* xdisplay = base::MessagePumpAuraX11::GetDefaultXDisplay();
   return gfx::Size(DisplayWidth(xdisplay, 0), DisplayHeight(xdisplay, 0));
 }
 
 }  // namespace aura