Revert of Stop calling blink::shutdown (patchset #9 id:160001 of https://codereview.chromium.org/22…

content/renderer/render_thread_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/render_thread_impl.h"
 
 #include <algorithm>
 #include <limits>
 #include <map>
 #include <utility>
@@ skipping 946 matching lines @@
     gpu_channel_->DestroyChannel();
 
   ChildThreadImpl::Shutdown();
 
   // Shut down the message loop (if provided when the RenderThreadImpl was
   // constructed) and the renderer scheduler before shutting down Blink. This
   // prevents a scenario where a pending task in the message loop accesses Blink
   // objects after Blink shuts down.
   renderer_scheduler_->SetRAILModeObserver(nullptr);
   renderer_scheduler_->Shutdown();
-
-  ChildThreadImpl::ShutdownDiscardableSharedMemoryManager();
-
   if (main_message_loop_)
     base::RunLoop().RunUntilIdle();
 
+  if (blink_platform_impl_) {
+    blink_platform_impl_->Shutdown();
+    // This must be at the very end of the shutdown sequence.
+    // blink::shutdown() must be called after all strong references from
+    // Chromium to Blink are cleared.
+    blink::shutdown();
+  }
+
+  // Delay shutting down DiscardableSharedMemoryManager until blink::shutdown
+  // is complete, because blink::shutdown destructs Blink Resources and they
+  // may try to unlock their underlying discardable memory.
+  ChildThreadImpl::ShutdownDiscardableSharedMemoryManager();
+
+  // The message loop must be cleared after shutting down
+  // the DiscardableSharedMemoryManager, which needs to send messages
+  // to the browser process.
   main_message_loop_.reset();
 
   lazy_tls.Pointer()->Set(nullptr);
 }
 
 bool RenderThreadImpl::Send(IPC::Message* msg) {
   // There are cases where we want to pump asynchronous messages while waiting
   // synchronously for the replies to the message to be sent here. However, this
   // may create an opportunity for re-entrancy into WebKit and other subsystems,
   // so we need to take care to disable callbacks, timers, and pending network
@@ skipping 1230 matching lines @@
   if (blink::mainThreadIsolate()) {
     blink::mainThreadIsolate()->MemoryPressureNotification(
         v8::MemoryPressureLevel::kCritical);
     blink::MemoryPressureNotificationToWorkerThreadIsolates(
         v8::MemoryPressureLevel::kCritical);
   }
 }
 
 
 }  // namespace content