Resume a backgrounded renderer that was purged and suspended

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 1746 matching lines @@
 
 void RenderThreadImpl::OnProcessPurgeAndSuspend() {
   ChildThreadImpl::OnProcessPurgeAndSuspend();
   if (is_renderer_suspended_)
     return;
   // TODO(hajimehoshi): Implement purging e.g. cache (crbug/607077)
   is_renderer_suspended_ = true;
   renderer_scheduler_->SuspendRenderer();
 }
 
+void RenderThreadImpl::OnProcessResume() {
+  ChildThreadImpl::OnProcessResume();
+  if (!is_renderer_suspended_)
+    return;
+
+  is_renderer_suspended_ = false;
+  renderer_scheduler_->ResumeRenderer();
+}
+
 void RenderThreadImpl::OnCreateNewFrame(FrameMsg_NewFrame_Params params) {
   // Debug cases of https://crbug.com/626802.
   base::debug::SetCrashKeyValue("newframe_routing_id",
                                 base::IntToString(params.routing_id));
   base::debug::SetCrashKeyValue("newframe_proxy_id",
                                 base::IntToString(params.proxy_routing_id));
   base::debug::SetCrashKeyValue("newframe_opener_id",
                                 base::IntToString(params.opener_routing_id));
   base::debug::SetCrashKeyValue("newframe_parent_id",
                                 base::IntToString(params.parent_routing_id));
@@ skipping 532 matching lines @@
   if (blink::mainThreadIsolate()) {
     blink::mainThreadIsolate()->MemoryPressureNotification(
         v8::MemoryPressureLevel::kCritical);
     blink::MemoryPressureNotificationToWorkerThreadIsolates(
         v8::MemoryPressureLevel::kCritical);
   }
 }
 
 
 }  // namespace content