Defer setting "internalinstanceid" so that pending (and destroyed)

content/renderer/browser_plugin/browser_plugin.cc

 // Copyright 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/browser_plugin/browser_plugin.h"
 
 #include "base/command_line.h"
 #include "base/message_loop/message_loop.h"
 #include "base/strings/string_number_conversions.h"
 #include "base/strings/utf_string_conversions.h"
@@ skipping 282 matching lines @@
     return false;
 
   container_ = container;
   container_->setWantsWheelEvents(true);
 
   g_plugin_container_map.Get().insert(std::make_pair(container_, this));
 
   BrowserPluginManager::Get()->AddBrowserPlugin(
       browser_plugin_instance_id_, this);
 
-  // This is a way to notify observers of our attributes that this plugin is
-  // available in render tree.
-  // TODO(lazyboy): This should be done through the delegate instead. Perhaps
-  // by firing an event from there.
-  UpdateDOMAttribute(
-      "internalinstanceid",
-      base::UTF8ToUTF16(base::IntToString(browser_plugin_instance_id_)));
-
+  // Defer attach call so that if there's any pending browser plugin
+  // destruction, then it can progress first.
+  base::MessageLoop::current()->PostTask(
+      FROM_HERE,
+      base::Bind(&BrowserPlugin::UpdateInternalInstanceId,
+                 weak_ptr_factory_.GetWeakPtr()));
   return true;
 }
 
 void BrowserPlugin::EnableCompositing(bool enable) {
   bool enabled = !!compositing_helper_.get();
   if (enabled == enable)
     return;
 
   if (enable) {
     DCHECK(!compositing_helper_.get());
     if (!compositing_helper_.get()) {
       compositing_helper_ = ChildFrameCompositingHelper::CreateForBrowserPlugin(
           weak_ptr_factory_.GetWeakPtr());
     }
   }
   compositing_helper_->EnableCompositing(enable);
   compositing_helper_->SetContentsOpaque(contents_opaque_);
 
   if (!enable) {
     DCHECK(compositing_helper_.get());
     compositing_helper_->OnContainerDestroy();
     compositing_helper_ = nullptr;
   }
 }
 
+void BrowserPlugin::UpdateInternalInstanceId() {
+  // This is a way to notify observers of our attributes that this plugin is
+  // available in render tree.
+  // TODO(lazyboy): This should be done through the delegate instead. Perhaps
+  // by firing an event from there.
+  UpdateDOMAttribute(
+      "internalinstanceid",
+      base::UTF8ToUTF16(base::IntToString(browser_plugin_instance_id_)));
+}
+
 void BrowserPlugin::destroy() {
   if (container_) {
     // The BrowserPlugin's WebPluginContainer is deleted immediately after this
     // call returns, so let's not keep a reference to it around.
     g_plugin_container_map.Get().erase(container_);
   }
 
   container_ = nullptr;
   // Will be a no-op if the mouse is not currently locked.
   auto render_frame = RenderFrameImpl::FromRoutingID(render_frame_routing_id());
@@ skipping 274 matching lines @@
 bool BrowserPlugin::HandleMouseLockedInputEvent(
     const blink::WebMouseEvent& event) {
   BrowserPluginManager::Get()->Send(
       new BrowserPluginHostMsg_HandleInputEvent(browser_plugin_instance_id_,
                                                 view_rect_,
                                                 &event));
   return true;
 }
 
 }  // namespace content