Created multi-process-friendly PowerMonitor interface.

base/power_monitor/power_monitor_device_source.cc

Index: base/power_monitor/power_monitor_device_source.cc
diff --git a/base/power_monitor/power_monitor_device_source.cc b/base/power_monitor/power_monitor_device_source.cc
new file mode 100644
index 0000000000000000000000000000000000000000..7405be12b05f423a44a503f16ee670242ec2aa93
--- /dev/null
+++ b/base/power_monitor/power_monitor_device_source.cc
@@ -0,0 +1,39 @@
+// Copyright 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 "base/power_monitor/power_monitor_device_source.h"
+
+#include "base/time.h"
+
+namespace base {
+
+#if defined(ENABLE_BATTERY_MONITORING)
+// The amount of time (in ms) to wait before running the initial
+// battery check.
+static int kDelayedBatteryCheckMs = 10 * 1000;
+#endif  // defined(ENABLE_BATTERY_MONITORING)
+
+PowerMonitorDeviceSource::PowerMonitorDeviceSource() {
+  DCHECK(MessageLoop::current());
+#if defined(ENABLE_BATTERY_MONITORING)
+  delayed_battery_check_.Start(FROM_HERE,
+      base::TimeDelta::FromMilliseconds(kDelayedBatteryCheckMs), this,
+      &PowerMonitorSource::BatteryCheck);
+#endif  // defined(ENABLE_BATTERY_MONITORING)
+#if defined(OS_MACOSX)
+  PlatformInit();
+#endif
+}
+
+PowerMonitorDeviceSource::~PowerMonitorDeviceSource() {
+#if defined(OS_MACOSX)
+  PlatformDestroy();
+#endif
+}
+
+void PowerMonitorDeviceSource::BatteryCheck() {
+  ProcessPowerEvent(PowerMonitorSource::POWER_STATE_EVENT);
+}
+
+}  // namespace base