Trace background/visibility events

content/browser/renderer_host/render_process_host_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.
 
 // Represents the browser side of the browser <--> renderer communication
 // channel. There will be one RenderProcessHost per renderer process.
 
 #include "content/browser/renderer_host/render_process_host_impl.h"
 
 #include <algorithm>
@@ skipping 2201 matching lines @@
 
 void RenderProcessHostImpl::OnSuddenTerminationChanged(bool enabled) {
   sudden_termination_allowed_ = enabled;
 }
 
 void RenderProcessHostImpl::OnDumpHandlesDone() {
   Cleanup();
 }
 
 void RenderProcessHostImpl::SetBackgrounded(bool backgrounded) {
+  TRACE_EVENT1("renderer_host", "RenderProcessHostImpl::SetBackgrounded",
+               "backgrounded", backgrounded);
   // Note: we always set the backgrounded_ value.  If the process is NULL
   // (and hence hasn't been created yet), we will set the process priority
   // later when we create the process.
   backgrounded_ = backgrounded;
   if (!child_process_launcher_.get() || child_process_launcher_->IsStarting())
     return;
 
   // Don't background processes which have active audio streams.
   if (backgrounded_ && audio_renderer_host_->HasActiveAudio())
     return;
@@ skipping 253 matching lines @@
   if (worker_ref_count_ == 0)
     Cleanup();
 }
 
 void RenderProcessHostImpl::GetAudioOutputControllers(
     const GetAudioOutputControllersCallback& callback) const {
   audio_renderer_host()->GetOutputControllers(callback);
 }
 
 }  // namespace content