Ensure that all NPN_PluginThreadAsyncCall callbacks are invoked before NPP_De...

webkit/glue/plugins/plugin_instance.cc

 // 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.
 
 #include "build/build_config.h"
 
 #include "webkit/glue/plugins/plugin_instance.h"
 
 #include "base/file_util.h"
 #include "base/message_loop.h"
@@ skipping 347 matching lines @@
 }
 
 void PluginInstance::PluginThreadAsyncCall(void (*func)(void *),
                                            void *user_data) {
   message_loop_->PostTask(FROM_HERE, NewRunnableMethod(
       this, &PluginInstance::OnPluginThreadAsyncCall, func, user_data));
 }
 
 void PluginInstance::OnPluginThreadAsyncCall(void (*func)(void *),
                                              void *user_data) {
-  func(user_data);
+  // Do not invoke the callback if NPP_Destroy has already been invoked.
+  if (webplugin_)
+    func(user_data);
 }
 
 uint32 PluginInstance::ScheduleTimer(uint32 interval,
                                      NPBool repeat,
                                      void (*func)(NPP id, uint32 timer_id)) {
   // Use next timer id.
   uint32 timer_id;
   timer_id = next_timer_id_;
   ++next_timer_id_;
   DCHECK(next_timer_id_ != 0);
@@ skipping 103 matching lines @@
           stream->url, range_info.c_str(),
           reinterpret_cast<intptr_t>(plugin_stream),
           plugin_stream->notify_needed(),
           reinterpret_cast<intptr_t>(plugin_stream->notify_data()));
       break;
     }
   }
 }
 
 }  // namespace NPAPI