Cancel drag if display configuration changes.

ui/aura/root_window_host_linux.cc

Index: ui/aura/root_window_host_linux.cc
diff --git a/ui/aura/root_window_host_linux.cc b/ui/aura/root_window_host_linux.cc
index a643c56b2fee672ea480664368c63ce48827fd8c..8ccf56acb426349a6e4e729f8b972b0c3075baee 100644
--- a/ui/aura/root_window_host_linux.cc
+++ b/ui/aura/root_window_host_linux.cc
@@ -1168,6 +1168,10 @@ void RootWindowHostLinux::OnDeviceScaleFactorChanged(
   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).