Revert r286729

content/child/process_background_message_filter.cc

Index: content/child/process_background_message_filter.cc
diff --git a/content/child/process_background_message_filter.cc b/content/child/process_background_message_filter.cc
deleted file mode 100644
index ee19d039b2a45c0bad61ea2cd45f4f55259cd8c8..0000000000000000000000000000000000000000
--- a/content/child/process_background_message_filter.cc
+++ /dev/null
@@ -1,46 +0,0 @@
-// Copyright 2014 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/child/process_background_message_filter.h"
-
-#include "base/process/process.h"
-#include "base/thread_task_runner_handle.h"
-#include "content/common/child_process_messages.h"
-
-namespace content {
-
-ProcessBackgroundMessageFilter::ProcessBackgroundMessageFilter()
-    : main_thread_task_runner_(base::ThreadTaskRunnerHandle::Get()) {
-}
-
-ProcessBackgroundMessageFilter::~ProcessBackgroundMessageFilter() {}
-
-bool ProcessBackgroundMessageFilter::OnMessageReceived(
-    const IPC::Message& message) {
-  bool handled = true;
-  IPC_BEGIN_MESSAGE_MAP(ProcessBackgroundMessageFilter, message)
-    IPC_MESSAGE_HANDLER(ChildProcessMsg_SetProcessBackgrounded,
-                        OnProcessBackgrounded)
-    IPC_MESSAGE_UNHANDLED(handled = false)
-  IPC_END_MESSAGE_MAP()
-  return handled;
-}
-
-void ProcessBackgroundMessageFilter::SetTimerSlack(bool background) {
-  DCHECK(thread_checker_.CalledOnValidThread());
-  // Set timer slack to maximum on main thread when in background.
-  base::MessageLoop::current()->SetTimerSlack(
-      background ? base::TIMER_SLACK_MAXIMUM : base::TIMER_SLACK_NONE);
-}
-
-void ProcessBackgroundMessageFilter::OnProcessBackgrounded(bool background) {
-  DCHECK(base::MessageLoopForIO::IsCurrent());
-  // Post to the main thread to set the timer slack.
-  main_thread_task_runner_->PostTask(
-      FROM_HERE,
-      base::Bind(
-          &ProcessBackgroundMessageFilter::SetTimerSlack, this, background));
-}
-
-}  // namespace content