Flush Xlib output buffer after calling XUngrabServer

ui/views/widget/desktop_aura/x11_whole_screen_move_loop.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/views/widget/desktop_aura/x11_whole_screen_move_loop.h"
 
 #include <X11/Xlib.h>
 // Get rid of a macro from Xlib.h that conflicts with Aura's RootWindow class.
 #undef RootWindow
 
@@ skipping 243 matching lines @@
         GrabModeAsync,
         GrabModeAsync,
         CurrentTime);
     if (ret != GrabSuccess) {
       DLOG(ERROR) << "Grabbing keyboard for dragging failed: "
                   << ui::GetX11ErrorString(display, ret);
     }
   }
 
   XUngrabServer(display);
+  XFlush(display);
   return ret == GrabSuccess;
 }
 
 Window X11WholeScreenMoveLoop::CreateDragInputWindow(XDisplay* display) {
   // Creates an invisible, InputOnly toplevel window. This window will receive
   // all mouse movement for drags. It turns out that normal windows doing a
   // grab doesn't redirect pointer motion events if the pointer isn't over the
   // grabbing window. But InputOnly windows are able to grab everything. This
   // is what GTK+ does, and I found a patch to KDE that did something similar.
   unsigned long attribute_mask = CWEventMask | CWOverrideRedirect;
@@ skipping 58 matching lines @@
     for (int x = 0; x < in_bitmap->width(); ++x) {
       if (SkColorGetA(in_row[x]) > kMinAlpha)
         return true;
     }
   }
 
   return false;
 }
 
 }  // namespace views