Make content::PowerSaveBlocker public

BUG=152207


Review URL: https://chromiumcodereview.appspot.com/11784016

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@176806 0039d316-1c4b-4281-b951-d872f2087c98

1 files changed, 46 insertions, 0 deletions

diff --git a/content/public/browser/power_save_blocker.h b/content/public/browser/power_save_blocker.h
new file mode 100644
index 0000000..fe9f966
--- /dev/null
+++ b/content/public/browser/power_save_blocker.h
@@ -0,0 +1,46 @@
+// 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.
+
+#ifndef CONTENT_PUBLIC_BROWSER_POWER_SAVE_BLOCKER_H_
+#define CONTENT_PUBLIC_BROWSER_POWER_SAVE_BLOCKER_H_
+
+#include <string>
+
+#include "base/basictypes.h"
+#include "base/memory/scoped_ptr.h"
+#include "content/common/content_export.h"
+
+namespace content {
+
+// A RAII-style class to block the system from entering low-power (sleep) mode.
+// This class is thread-safe; it may be constructed and deleted on any thread.
+class CONTENT_EXPORT PowerSaveBlocker {
+ public:
+  enum PowerSaveBlockerType {
+    // Prevent the application from being suspended. On some platforms, apps may
+    // be suspended when they are not visible to the user. This type of block
+    // requests that the app continue to run in that case, and on all platforms
+    // prevents the system from sleeping.
+    // Example use cases: downloading a file, playing audio.
+    kPowerSaveBlockPreventAppSuspension,
+
+    // Prevent the display from going to sleep. This also has the side effect of
+    // preventing the system from sleeping, but does not necessarily prevent the
+    // app from being suspended on some platforms if the user hides it.
+    // Example use case: playing video.
+    kPowerSaveBlockPreventDisplaySleep,
+  };
+
+  virtual ~PowerSaveBlocker() = 0;
+
+  // Pass in the type of power save blocking desired. If multiple types of
+  // blocking are desired, instantiate one PowerSaveBlocker for each type.
+  // |reason| may be provided to the underlying system APIs on some platforms.
+  static scoped_ptr<PowerSaveBlocker> Create(PowerSaveBlockerType type,
+                                             const std::string& reason);
+};
+
+}  // namespace content
+
+#endif  // CONTENT_PUBLIC_BROWSER_POWER_SAVE_BLOCKER_H_