Keep screen on when there is an active WebRTC session on Android.

content/browser/power_save_blocker_android.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 "base/logging.h"
+#include "content/browser/android/content_video_view.h"
+#include "content/public/browser/browser_thread.h"
 
 namespace content {
+namespace {
+int blocker_count = 0;
+}  // namespace
 
 class PowerSaveBlockerImpl::Delegate
-    : public base::RefCounted<PowerSaveBlockerImpl::Delegate> {
+    : public base::RefCountedThreadSafe<PowerSaveBlockerImpl::Delegate> {
+ public:
+  Delegate(PowerSaveBlockerType type)
+      : type_(type) {}

[qinmin, 2013/05/21 21:40:24]

nit: can move to a single line

[wjia(left Chromium), 2013/05/21 21:50:24]

Done.

+
+  // Does the actual work to apply or remove the desired power save block.
+  void ApplyBlock();
+  void RemoveBlock();
+
  private:
-  friend class base::RefCounted<Delegate>;
+  friend class base::RefCountedThreadSafe<Delegate>;
   ~Delegate() {}
+
+  PowerSaveBlockerType type_;
+
+  DISALLOW_COPY_AND_ASSIGN(Delegate);
 };
 
+void PowerSaveBlockerImpl::Delegate::ApplyBlock() {
+  DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
+  if (type_ == kPowerSaveBlockPreventDisplaySleep) {

[qinmin, 2013/05/21 21:40:24]

nit: remove nested loops.
if (type_ != kPowerSaveBlockPreventDisplaySleep)
  return;
if (blocker_count == 0)
  ContentVideoView::KeepScreenOn(true);
++blocker_count;

[wjia(left Chromium), 2013/05/21 21:50:24]

Done.

+    if (blocker_count == 0)
+      ContentVideoView::KeepScreenOn(true);
+    ++blocker_count;
+  }
+}
+
+void PowerSaveBlockerImpl::Delegate::RemoveBlock() {
+  DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
+  if (type_ == kPowerSaveBlockPreventDisplaySleep) {

[qinmin, 2013/05/21 21:40:24]

ditto

[wjia(left Chromium), 2013/05/21 21:50:24]

Done.

+    --blocker_count;
+    if (blocker_count == 0)
+      ContentVideoView::KeepScreenOn(false);
+  }
+}
+
 PowerSaveBlockerImpl::PowerSaveBlockerImpl(PowerSaveBlockerType type,
-                                           const std::string& reason) {
-  // TODO(wangxianzhu): Implement it.
+                                           const std::string& reason)
+    : delegate_(new Delegate(type)) {
   // This may be called on any thread.
-  NOTIMPLEMENTED();
+  BrowserThread::PostTask(
+      BrowserThread::UI, FROM_HERE,
+      base::Bind(&Delegate::ApplyBlock, delegate_));
 }
 
 PowerSaveBlockerImpl::~PowerSaveBlockerImpl() {
+  BrowserThread::PostTask(
+      BrowserThread::UI, FROM_HERE,
+      base::Bind(&Delegate::RemoveBlock, delegate_));
 }
 
 }  // namespace content