Add screen power save block level.

content/browser/power_save_blocker_stub.cc

Index: content/browser/power_save_blocker_stub.cc
diff --git a/content/browser/power_save_blocker_stub.cc b/content/browser/power_save_blocker_stub.cc
index 701d1e53f1c890e13b8e88cf0d58bbf2172bd577..52636101d509c341e0853382a271de33b92e4572 100644
--- a/content/browser/power_save_blocker_stub.cc
+++ b/content/browser/power_save_blocker_stub.cc
@@ -1,4 +1,4 @@
-// Copyright (c) 2010 The Chromium Authors. All rights reserved.
+// Copyright (c) 2011 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.
 
@@ -6,6 +6,8 @@
 
 // Default, stub implementation, for platforms that don't have their own yet.
 
-void PowerSaveBlocker::ApplyBlock(bool blocking) {
+// Called only from UI thread.
+// static
+void PowerSaveBlocker::ApplyBlock(PowerSaveBlockerType type) {
   // http://code.google.com/p/chromium/issues/detail?id=33605
 }