Don't load plugins on prerendered pages until the pages are displayed....

chrome/common/render_messages_params.cc

 // Copyright (c) 2010 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 "chrome/common/render_messages_params.h"
 
 #include "chrome/common/navigation_gesture.h"
 #include "chrome/common/common_param_traits.h"
 #include "chrome/common/render_messages.h"
 #include "net/base/upload_data.h"
@@ skipping 298 matching lines @@
         break;
 
       case ViewMsg_Navigate_Params::RELOAD_IGNORING_CACHE:
         event = "NavigationType_RELOAD_IGNORING_CACHE";
         break;
 
       case ViewMsg_Navigate_Params::RESTORE:
         event = "NavigationType_RESTORE";
         break;
 
+      case ViewMsg_Navigate_Params::PRERENDER:
+        event = "NavigationType_PRERENDER";
+        break;
+
       case ViewMsg_Navigate_Params::NORMAL:
         event = "NavigationType_NORMA";
         break;
 
       default:
         event = "NavigationType_UNKNOWN";
         break;
     }
     LogParam(event, l);
   }
@@ skipping 1277 matching lines @@
     const param_type& p,
     std::string* l) {
   l->append("(");
   LogParam(p.notification_type, l);
   l->append(", ");
   LogParam(p.acc_obj, l);
   l->append(")");
 }
 
 }  // namespace IPC