Experimental 'purging and suspending' backgrounded tabs behind the flag

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 1720 matching lines @@
 
 void RenderThreadImpl::OnProcessBackgrounded(bool backgrounded) {
   ChildThreadImpl::OnProcessBackgrounded(backgrounded);
 
   if (backgrounded)
     renderer_scheduler_->OnRendererBackgrounded();
   else
     renderer_scheduler_->OnRendererForegrounded();
 }
 
+void RenderThreadImpl::OnProcessPurgeAndSuspend() {
+  ChildThreadImpl::OnProcessPurgeAndSuspend();
+  renderer_scheduler_->OnRendererPurgeAndSuspend();
+}
+
 void RenderThreadImpl::OnCreateNewFrame(FrameMsg_NewFrame_Params params) {
   CompositorDependencies* compositor_deps = this;
   RenderFrameImpl::CreateFrame(
       params.routing_id, params.proxy_routing_id, params.opener_routing_id,
       params.parent_routing_id, params.previous_sibling_routing_id,
       params.replication_state, compositor_deps, params.widget_params,
       params.frame_owner_properties);
 }
 
 void RenderThreadImpl::OnCreateNewFrameProxy(
@@ skipping 358 matching lines @@
 }
 
 void RenderThreadImpl::PendingRenderFrameConnect::OnConnectionError() {
   size_t erased =
       RenderThreadImpl::current()->pending_render_frame_connects_.erase(
           routing_id_);
   DCHECK_EQ(1u, erased);
 }
 
 }  // namespace content