Reland: Fix WebViewPlugin::scheduleAnimation crash

content/renderer/pepper/pepper_plugin_instance_impl.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 "content/renderer/pepper/pepper_plugin_instance_impl.h"
 
 #include "base/bind.h"
 #include "base/callback_helpers.h"
 #include "base/logging.h"
 #include "base/memory/linked_ptr.h"
@@ skipping 652 matching lines @@
 void PepperPluginInstanceImpl::Delete() {
   is_deleted_ = true;
 
   if (render_frame_ && render_frame_->render_view() &&
       render_frame_->render_view()->plugin_find_handler() == this) {
     render_frame_->render_view()->set_plugin_find_handler(NULL);
   }
 
   // Keep a reference on the stack. See NOTE above.
   scoped_refptr<PepperPluginInstanceImpl> ref(this);
+
+  // It is important to destroy the throttler before anything else.
+  // The plugin instance may flush its graphics pipeline during its postmortem
+  // spasm, causing the throttler to engage and obtain new dangling reference
+  // to the plugin container being destroyed.
+  throttler_.reset();
+
   // Force the MessageChannel to release its "passthrough object" which should
   // release our last reference to the "InstanceObject" and will probably
   // destroy it. We want to do this prior to calling DidDestroy in case the
   // destructor of the instance object tries to use the instance.
   if (message_channel_)
     message_channel_->SetPassthroughObject(v8::Local<v8::Object>());
   // If this is a NaCl plugin instance, shut down the NaCl plugin by calling
   // its DidDestroy. Don't call DidDestroy on the untrusted plugin instance,
   // since there is little that it can do at this point.
   if (original_instance_interface_) {
@@ skipping 2659 matching lines @@
 
 void PepperPluginInstanceImpl::RecordFlashJavaScriptUse() {
   if (initialized_ && !javascript_used_ && is_flash_plugin_) {
     javascript_used_ = true;
     RenderThread::Get()->RecordAction(
         base::UserMetricsAction("Flash.JavaScriptUsed"));
   }
 }
 
 }  // namespace content