Add chrome.power extension API.

chrome/browser/extensions/api/power/power_api.cc

+// Copyright (c) 2013 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 "chrome/browser/extensions/api/power/power_api.h"
+
+#include "chrome/browser/extensions/api/power/power_api_manager.h"
+#include "chrome/common/extensions/api/power.h"
+
+namespace extensions {
+
+bool PowerRequestKeepAwakeFunction::RunImpl() {
+  scoped_ptr<api::power::RequestKeepAwake::Params> params(
+      api::power::RequestKeepAwake::Params::Create(*args_));
+  EXTENSION_FUNCTION_VALIDATE(params);
+  PowerApiManager::GetInstance()->AddRequest(extension_id(),
+      params->level == api::power::LEVEL_NONE ? api::power::LEVEL_DISPLAY :

[not at google - send to devlin, 2013/03/20 00:25:50]

seems like PowerApiManager needs to deal with the NONE value already, so might
as well pass through params->level and normalize it there.

P.S. it can't possibly be NONE - schema compiler guarantees it (so in fact you
could EXTENSION_FUNCITON_VALIDATE(params->level != NONE) if you wanted). I tried
to make the schema compiler not generate it but it ended up being too much of a
yak.

[Daniel Erat, 2013/03/20 00:47:46]

Ah, okay; I figured that NONE was there for optional params.  I'll just make it
non-optional and _VALIDATE here.

+      params->level);
+  return true;
+}
+
+bool PowerReleaseKeepAwakeFunction::RunImpl() {
+  PowerApiManager::GetInstance()->RemoveRequest(extension_id());
+  return true;
+}
+
+}  // namespace extensions