Created multi-process-friendly PowerMonitor interface.

content/child/power_monitor_broadcast_source.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 "content/child/power_monitor_broadcast_source.h"
+
+#include "content/common/power_monitor_messages.h"
+
+namespace content {
+
+PowerMonitorBroadcastSource::PowerMonitorBroadcastSource(
+    scoped_refptr<base::MessageLoopProxy> message_loop)
+    : last_reported_battery_power_state_(false),
+      weak_factory_(this) {
+  message_filter_ = new PowerMessageFilter(weak_factory_.GetWeakPtr(),
+      message_loop);
+}
+
+PowerMonitorBroadcastSource::~PowerMonitorBroadcastSource() {
+}
+
+// MessageFilters are owned by the Channel they are added to, so this class does
+// not need to retain a reference.

[piman, 2013/07/29 21:18:18]

nit: ... but it does anyway, making this comment misleading more than anything
else. Just remove?

+IPC::ChannelProxy::MessageFilter*
+PowerMonitorBroadcastSource::MessageFilter() {
+  return message_filter_.get();
+}
+
+bool PowerMonitorBroadcastSource::IsOnBatteryPowerImpl() {
+  return last_reported_battery_power_state_;
+}
+
+void PowerMonitorBroadcastSource::OnPowerStateChange(bool on_battery_power) {
+  last_reported_battery_power_state_ = on_battery_power;
+  ProcessPowerEvent(PowerMonitorSource::POWER_STATE_EVENT);
+}
+
+void PowerMonitorBroadcastSource::OnSuspend() {
+  ProcessPowerEvent(PowerMonitorSource::SUSPEND_EVENT);
+}
+
+void PowerMonitorBroadcastSource::OnResume() {
+  ProcessPowerEvent(PowerMonitorSource::RESUME_EVENT);
+}
+
+PowerMonitorBroadcastSource::PowerMessageFilter::PowerMessageFilter(
+    base::WeakPtr<PowerMonitorBroadcastSource> source,
+    scoped_refptr<base::MessageLoopProxy> message_loop)
+    : source_(source),
+      message_loop_(message_loop) {
+}
+
+PowerMonitorBroadcastSource::PowerMessageFilter::~PowerMessageFilter() {
+}
+
+bool PowerMonitorBroadcastSource::PowerMessageFilter::OnMessageReceived(
+    const IPC::Message& message) {
+  bool msg_is_ok = false;
+  bool handled = true;
+  IPC_BEGIN_MESSAGE_MAP_EX(PowerMessageFilter, message, msg_is_ok)
+    IPC_MESSAGE_HANDLER(PowerMonitorMsg_PowerStateChange, OnPowerStateChange)
+    IPC_MESSAGE_HANDLER(PowerMonitorMsg_Suspend, OnSuspend)
+    IPC_MESSAGE_HANDLER(PowerMonitorMsg_Resume, OnResume)
+    IPC_MESSAGE_UNHANDLED(handled = false)
+  IPC_END_MESSAGE_MAP_EX()
+  return handled && msg_is_ok;
+}
+
+void PowerMonitorBroadcastSource::PowerMessageFilter::OnPowerStateChange(
+    bool on_battery_power) {
+  message_loop_->PostTask(FROM_HERE,
+      base::Bind(&PowerMonitorBroadcastSource::OnPowerStateChange, source_,
+          on_battery_power));
+}
+
+void PowerMonitorBroadcastSource::PowerMessageFilter::OnSuspend() {
+  message_loop_->PostTask(FROM_HERE,
+      base::Bind(&PowerMonitorBroadcastSource::OnSuspend, source_));
+}
+
+void PowerMonitorBroadcastSource::PowerMessageFilter::OnResume() {
+  message_loop_->PostTask(FROM_HERE,
+      base::Bind(&PowerMonitorBroadcastSource::OnResume, source_));
+}
+
+}  // namespace content