Avoid blocking while mapping an X11 window

ui/events/platform/x11/x11_event_source.cc

 // Copyright 2014 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/events/platform/x11/x11_event_source.h"
 
 #include <X11/Xatom.h>
 #include <X11/XKBlib.h>
 #include <X11/Xlib.h>
 
@@ skipping 130 matching lines @@
 }
 
 void X11EventSource::DispatchXEventNow(XEvent* event) {
   ExtractCookieDataDispatchEvent(event);
 }
 
 void X11EventSource::BlockUntilWindowMapped(XID window) {
   BlockOnWindowStructureEvent(window, MapNotify);
 }
 
-void X11EventSource::BlockUntilWindowUnmapped(XID window) {
-  BlockOnWindowStructureEvent(window, UnmapNotify);
-}
-
 Time X11EventSource::GetCurrentServerTime() {
   DCHECK(display_);
 
   if (!dummy_initialized_) {
     // Create a new Window and Atom that will be used for the property change.
     dummy_window_ = XCreateSimpleWindow(display_, DefaultRootWindow(display_),
                                         0, 0, 1, 1, 0, 0, 0);
     dummy_atom_ = XInternAtom(display_, "CHROMIUM_TIMESTAMP", False);
     XSelectInput(display_, dummy_window_, PropertyChangeMask);
     dummy_initialized_ = true;
@@ skipping 93 matching lines @@
 
 void X11EventSource::OnDispatcherListChanged() {
   if (!hotplug_event_handler_) {
     hotplug_event_handler_.reset(new X11HotplugEventHandler());
     // Force the initial device query to have an update list of active devices.
     hotplug_event_handler_->OnHotplugEvent();
   }
 }
 
 }  // namespace ui