[Prerender] Change IPC from bool to enum for more prerender modes

chrome/renderer/plugins/chrome_plugin_placeholder.h

 // Copyright 2013 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 CHROME_RENDERER_PLUGINS_CHROME_PLUGIN_PLACEHOLDER_H_
 #define CHROME_RENDERER_PLUGINS_CHROME_PLUGIN_PLACEHOLDER_H_
 
 #include <stdint.h>
 
 #include "base/macros.h"
+#include "chrome/common/prerender_types.h"
 #include "chrome/renderer/plugins/power_saver_info.h"
 #include "components/plugins/renderer/loadable_plugin_placeholder.h"
 #include "content/public/renderer/context_menu_client.h"
 #include "content/public/renderer/render_thread_observer.h"
 
 enum class ChromeViewHostMsg_GetPluginInfo_Status;
 
 class ChromePluginPlaceholder final
     : public plugins::LoadablePluginPlaceholder,
       public content::RenderThreadObserver,
@@ skipping 64 matching lines @@
 
   // IPC message handlers:
 #if defined(ENABLE_PLUGIN_INSTALLATION)
   void OnDidNotFindMissingPlugin();
   void OnFoundMissingPlugin(const base::string16& plugin_name);
   void OnStartedDownloadingPlugin();
   void OnFinishedDownloadingPlugin();
   void OnErrorDownloadingPlugin(const std::string& error);
   void OnCancelledDownloadingPlugin();
 #endif
+  void OnSetPrerenderMode(prerender::PrerenderMode mode);
 
   ChromeViewHostMsg_GetPluginInfo_Status status_;
 
   base::string16 title_;
 
 #if defined(ENABLE_PLUGIN_INSTALLATION)
   // |routing_id()| is the routing ID of our associated RenderView, but we have
   // a separate routing ID for messages specific to this placeholder.
   int32_t placeholder_routing_id_ = MSG_ROUTING_NONE;
 
   bool has_host_ = false;
 #endif
 
   int context_menu_request_id_;  // Nonzero when request pending.
   base::string16 plugin_name_;
 
   bool did_send_blocked_content_notification_;
 
   DISALLOW_COPY_AND_ASSIGN(ChromePluginPlaceholder);
 };
 
 #endif  // CHROME_RENDERER_PLUGINS_CHROME_PLUGIN_PLACEHOLDER_H_