Revert 189518 "PPAPI: Remove threading options; it's always on"

trunk/src/ppapi/proxy/plugin_globals.h

 // 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.
 
 #ifndef PPAPI_PROXY_PLUGIN_GLOBALS_H_
 #define PPAPI_PROXY_PLUGIN_GLOBALS_H_
 
 #include <string>
 
 #include "base/compiler_specific.h"
@@ skipping 96 matching lines @@
   // long as the plugin.
   MessageLoopResource* loop_for_main_thread();
 
   // The embedder should call this function when the name of the plugin module
   // is known. This will be used for error logging.
   void set_plugin_name(const std::string& name) { plugin_name_ = name; }
 
   // The embedder should call this function when the command line is known.
   void set_command_line(const std::string& c) { command_line_ = c; }
 
+  // Sets whether threadsafety is supported. Defaults to whether the
+  // ENABLE_PEPPER_THREADING build flag is set.
+  void set_enable_threading(bool enable) { enable_threading_ = enable; }
+
  private:
   class BrowserSender;
 
   // PpapiGlobals overrides.
   virtual bool IsPluginGlobals() const OVERRIDE;
 
   static PluginGlobals* plugin_globals_;
 
   PluginProxyDelegate* plugin_proxy_delegate_;
   PluginResourceTracker plugin_resource_tracker_;
   PluginVarTracker plugin_var_tracker_;
   scoped_refptr<CallbackTracker> callback_tracker_;
 
+  bool enable_threading_;  // Indicates whether we'll use the lock.
   base::Lock proxy_lock_;
 
   scoped_ptr<base::ThreadLocalStorage::Slot> msg_loop_slot_;
   // Note that loop_for_main_thread's constructor sets msg_loop_slot_, so it
   // must be initialized after msg_loop_slot_ (hence the order here).
   scoped_refptr<MessageLoopResource> loop_for_main_thread_;
 
   // Name of the plugin used for error logging. This will be empty until
   // set_plugin_name is called.
   std::string plugin_name_;
 
   // Command line for the plugin. This will be empty until set_command_line is
   // called.
   std::string command_line_;
 
   scoped_ptr<BrowserSender> browser_sender_;
 
   DISALLOW_COPY_AND_ASSIGN(PluginGlobals);
 };
 
 }  // namespace proxy
 }  // namespace ppapi
 
 #endif   // PPAPI_PROXY_PLUGIN_GLOBALS_H_