Reland of 'Move content/browser/power_save_blocker to //device/power_save_blocker'

content/browser/power_save_blocker_mac.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/browser/power_save_blocker_impl.h"
-
-#include <IOKit/pwr_mgt/IOPMLib.h>
-
-#include "base/bind.h"
-#include "base/lazy_instance.h"
-#include "base/mac/scoped_cftyperef.h"
-#include "base/strings/sys_string_conversions.h"
-#include "base/threading/platform_thread.h"
-#include "base/threading/thread.h"
-
-namespace content {
-namespace {
-
-// Power management cannot be done on the UI thread. IOPMAssertionCreate does a
-// synchronous MIG call to configd, so if it is called on the main thread the UI
-// is at the mercy of another process. See http://crbug.com/79559 and
-// http://www.opensource.apple.com/source/IOKitUser/IOKitUser-514.16.31/pwr_mgt.subproj/IOPMLibPrivate.c .
-struct PowerSaveBlockerLazyInstanceTraits {
-  static const bool kRegisterOnExit = false;
-#ifndef NDEBUG
-  static const bool kAllowedToAccessOnNonjoinableThread = true;
-#endif
-
-  static base::Thread* New(void* instance) {
-    base::Thread* thread = new (instance) base::Thread("PowerSaveBlocker");
-    thread->Start();
-    return thread;
-  }
-  static void Delete(base::Thread* instance) { }
-};
-base::LazyInstance<base::Thread, PowerSaveBlockerLazyInstanceTraits>
-    g_power_thread = LAZY_INSTANCE_INITIALIZER;
-
-}  // namespace
-
-class PowerSaveBlockerImpl::Delegate
-    : public base::RefCountedThreadSafe<PowerSaveBlockerImpl::Delegate> {
- public:
-  Delegate(PowerSaveBlockerType type, const std::string& description)
-      : type_(type),
-        description_(description),
-        assertion_(kIOPMNullAssertionID) {}
-
-  // Does the actual work to apply or remove the desired power save block.
-  void ApplyBlock();
-  void RemoveBlock();
-
- private:
-  friend class base::RefCountedThreadSafe<Delegate>;
-  ~Delegate() {}
-  PowerSaveBlockerType type_;
-  std::string description_;
-  IOPMAssertionID assertion_;
-};
-
-void PowerSaveBlockerImpl::Delegate::ApplyBlock() {
-  DCHECK_EQ(base::PlatformThread::CurrentId(),
-            g_power_thread.Pointer()->GetThreadId());
-
-  CFStringRef level = NULL;
-  // See QA1340 <http://developer.apple.com/library/mac/#qa/qa1340/> for more
-  // details.
-  switch (type_) {
-    case PowerSaveBlocker::kPowerSaveBlockPreventAppSuspension:
-      level = kIOPMAssertionTypeNoIdleSleep;
-      break;
-    case PowerSaveBlocker::kPowerSaveBlockPreventDisplaySleep:
-      level = kIOPMAssertionTypeNoDisplaySleep;
-      break;
-    default:
-      NOTREACHED();
-      break;
-  }
-  if (level) {
-    base::ScopedCFTypeRef<CFStringRef> cf_description(
-        base::SysUTF8ToCFStringRef(description_));
-    IOReturn result = IOPMAssertionCreateWithName(level, kIOPMAssertionLevelOn,
-                                                  cf_description, &assertion_);
-    LOG_IF(ERROR, result != kIOReturnSuccess)
-        << "IOPMAssertionCreate: " << result;
-  }
-}
-
-void PowerSaveBlockerImpl::Delegate::RemoveBlock() {
-  DCHECK_EQ(base::PlatformThread::CurrentId(),
-            g_power_thread.Pointer()->GetThreadId());
-
-  if (assertion_ != kIOPMNullAssertionID) {
-    IOReturn result = IOPMAssertionRelease(assertion_);
-    LOG_IF(ERROR, result != kIOReturnSuccess)
-        << "IOPMAssertionRelease: " << result;
-  }
-}
-
-PowerSaveBlockerImpl::PowerSaveBlockerImpl(
-    PowerSaveBlockerType type,
-    Reason reason,
-    const std::string& description,
-    scoped_refptr<base::SequencedTaskRunner> ui_task_runner,
-    scoped_refptr<base::SingleThreadTaskRunner> blocking_task_runner)
-    : delegate_(new Delegate(type, description)),
-      ui_task_runner_(ui_task_runner),
-      blocking_task_runner_(blocking_task_runner) {
-  g_power_thread.Pointer()->message_loop()->PostTask(
-      FROM_HERE,
-      base::Bind(&Delegate::ApplyBlock, delegate_));
-}
-
-PowerSaveBlockerImpl::~PowerSaveBlockerImpl() {
-  g_power_thread.Pointer()->message_loop()->PostTask(
-      FROM_HERE,
-      base::Bind(&Delegate::RemoveBlock, delegate_));
-}
-
-}  // namespace content