Revert of Chrome power profiler service

content/browser/power_profiler/power_profiler_service.cc

-// 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/browser/power_profiler/power_profiler_service.h"
-
-#include "base/bind.h"
-#include "base/message_loop/message_loop.h"
-#include "base/threading/sequenced_worker_pool.h"
-#include "content/public/browser/browser_thread.h"
-
-namespace {
-
-// Default sampling period, as recommended by Intel Power Gadget.
-// Section 3.1 of http://software.intel.com/en-us/blogs/2013/10/03/using-the-intel-power-gadget-api-on-windows
-const int kDefaultSamplePeriodMs = 50;
-
-}  // namespace
-
-namespace content {
-
-PowerProfilerService::PowerProfilerService()
-    : status_(UNINITIALIZED),
-      sample_period_(base::TimeDelta::FromMilliseconds(kDefaultSamplePeriodMs)),
-      data_provider_(PowerDataProvider::Create()) {
-  DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
-
-  // No provider supported for current platform.
-  if (!data_provider_.get())
-    return;
-
-  status_ = INITIALIZED;
-  task_runner_ = BrowserThread::GetBlockingPool()->GetSequencedTaskRunner(
-      BrowserThread::GetBlockingPool()->GetSequenceToken());
-}
-
-PowerProfilerService::PowerProfilerService(
-    scoped_ptr<PowerDataProvider> provider,
-    scoped_refptr<base::TaskRunner> task_runner,
-    const base::TimeDelta& sample_period)
-    : task_runner_(task_runner),
-      status_(UNINITIALIZED),
-      sample_period_(sample_period),
-      data_provider_(provider.Pass()) {
-  DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
-
-  if (data_provider_.get())
-      status_ = INITIALIZED;
-}
-
-PowerProfilerService::~PowerProfilerService() {
-}
-
-bool PowerProfilerService::IsAvailable() {
-  return status_ !=  UNINITIALIZED;
-}
-
-PowerProfilerService* PowerProfilerService::GetInstance() {
-  return Singleton<PowerProfilerService>::get();
-}
-
-void PowerProfilerService::AddObserver(PowerProfilerObserver* observer) {
-  if (status_ == UNINITIALIZED)
-    return;
-
-  observers_.AddObserver(observer);
-  if (status_ != PROFILING)
-    Start();
-}
-
-void PowerProfilerService::RemoveObserver(PowerProfilerObserver* observer) {
-  observers_.RemoveObserver(observer);
-
-  if (!observers_.might_have_observers())
-    Stop();
-}
-
-void PowerProfilerService::Start() {
-  DCHECK(status_ == INITIALIZED);
-  status_ = PROFILING;
-
-  // Send out power events immediately.
-  QueryData();
-
-  query_power_timer_.Start(FROM_HERE,
-      sample_period_, this, &PowerProfilerService::QueryData);
-}
-
-void PowerProfilerService::Stop() {
-  DCHECK(status_ == PROFILING);
-
-  query_power_timer_.Stop();
-  status_ = INITIALIZED;
-}
-
-void PowerProfilerService::QueryData() {
-  task_runner_->PostTask(
-      FROM_HERE, base::Bind(&PowerProfilerService::QueryDataOnTaskRunner,
-                            base::Unretained(this)));
-}
-
-void PowerProfilerService::Notify(const PowerEventVector& events) {
-  FOR_EACH_OBSERVER(PowerProfilerObserver, observers_, OnPowerEvent(events));
-}
-
-void PowerProfilerService::QueryDataOnTaskRunner() {
-  DCHECK(task_runner_->RunsTasksOnCurrentThread());
-  DCHECK(status_ == PROFILING);
-
-  // Get data and notify.
-  PowerEventVector events = data_provider_->GetData();
-  if (events.size() != 0) {
-    BrowserThread::PostTask(BrowserThread::UI, FROM_HERE, base::Bind(
-        &PowerProfilerService::Notify, base::Unretained(this), events));
-  }
-}
-
-}  // namespace content