Linux: move X operations from the IO to UI2 thread.

chrome/browser/browser_process.h

 // Copyright (c) 2006-2008 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.
 
 // This interfaces is for managing the global services of the application. Each
 // service is lazily created when requested the first time. The service getters
 // will return NULL if the service is not available, so callers must check for
 // this condition.
 
 #ifndef CHROME_BROWSER_BROWSER_PROCESS_H_
@@ skipping 78 matching lines @@
   // Returns the thread that we perform random file operations on. For code
   // that wants to do I/O operations (not network requests or even file: URL
   // requests), this is the thread to use to avoid blocking the UI thread.
   // It might be nicer to have a thread pool for this kind of thing.
   virtual base::Thread* file_thread() = 0;
 
   // Returns the thread that is used for database operations such as the web
   // database. History has its own thread since it has much higher traffic.
   virtual base::Thread* db_thread() = 0;
 
+#if defined(OS_LINUX)
+  // Returns the thread that is used to process UI requests in cases were
+  // we can't route the request to the UI thread. Note that this thread
+  // should only be used by the IO thread and this method is only safe to call
+  // from the UI thread so, if you've ended up here, something has gone wrong.
+  // This method is only included for uniformity.
+  virtual base::Thread* background_x11_thread() = 0;
+#endif
+
   virtual sandbox::BrokerServices* broker_services() = 0;
 
   virtual IconManager* icon_manager() = 0;
 
   virtual void InitBrokerServices(sandbox::BrokerServices*) = 0;
   virtual AutomationProviderList* InitAutomationProviderList() = 0;
 
   virtual void InitDebuggerWrapper(int port) = 0;
 
   virtual unsigned int AddRefModule() = 0;
@@ skipping 27 matching lines @@
  private:
   // User-data-dir based profiles.
   std::vector<std::wstring> user_data_dir_profiles_;
 
   DISALLOW_COPY_AND_ASSIGN(BrowserProcess);
 };
 
 extern BrowserProcess* g_browser_process;
 
 #endif  // CHROME_BROWSER_BROWSER_PROCESS_H_