Keep NaCl plugins used in app background pages alive when active.

ppapi/shared_impl/ppapi_globals.cc

 // 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.
 
 #include "ppapi/shared_impl/ppapi_globals.h"
 
 #include "base/lazy_instance.h"  // For testing purposes only.
 #include "base/logging.h"
 #include "base/message_loop/message_loop_proxy.h"
 #include "base/threading/thread_local.h"  // For testing purposes only.
@@ skipping 51 matching lines @@
 }
 
 bool PpapiGlobals::IsHostGlobals() const {
   return false;
 }
 
 bool PpapiGlobals::IsPluginGlobals() const {
   return false;
 }
 
+void PpapiGlobals::MarkPluginIsActive() {
+}
+
 // static
 PpapiGlobals* PpapiGlobals::GetThreadLocalPointer() {
   return tls_ppapi_globals_for_test.Pointer()->Get();
 }
 
 }  // namespace ppapi