Move X11 device processing to worker threads

ui/events/platform/x11/x11_event_source.h

 // 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.
 
 #ifndef UI_EVENTS_PLATFORM_X11_X11_EVENT_SOURCE_H_
 #define UI_EVENTS_PLATFORM_X11_X11_EVENT_SOURCE_H_
 
 #include "base/memory/scoped_ptr.h"
 #include "ui/events/events_export.h"
 #include "ui/events/platform/platform_event_source.h"
@@ skipping 32 matching lines @@
   // functions which require a mapped window.
   void BlockUntilWindowMapped(XID window);
 
  protected:
   XDisplay* display() { return display_; }
 
  private:
   // PlatformEventSource:
   uint32_t DispatchEvent(XEvent* xevent) override;
   void StopCurrentEventStream() override;
+  void OnDispatcherListChanged() override;
 
   // The connection to the X11 server used to receive the events.
   XDisplay* display_;
 
   // Keeps track of whether this source should continue to dispatch all the
   // available events.
   bool continue_stream_;
 
   scoped_ptr<X11HotplugEventHandler> hotplug_event_handler_;
 
   DISALLOW_COPY_AND_ASSIGN(X11EventSource);
 };
 
 }  // namespace ui
 
 #endif  // UI_EVENTS_PLATFORM_X11_X11_EVENT_SOURCE_H_