Add policies to control power management on the Chrome OS login screen

chromeos/dbus/power_policy_controller.cc

Index: chromeos/dbus/power_policy_controller.cc
diff --git a/chromeos/dbus/power_policy_controller.cc b/chromeos/dbus/power_policy_controller.cc
index 5edc5bd9fd3a63d1792b4706c10c4b47ac150714..5d1c8ae543d867794e632d6245233e25fad0fb49 100644
--- a/chromeos/dbus/power_policy_controller.cc
+++ b/chromeos/dbus/power_policy_controller.cc
@@ -157,8 +157,9 @@ void PowerPolicyController::ApplyPrefs(const PrefValues& values) {
   int64 lock_ms = delays->screen_off_ms() + kScreenLockAfterOffDelayMs;
   if (values.enable_screen_lock && delays->screen_off_ms() > 0 &&
       (delays->screen_lock_ms() <= 0 || lock_ms < delays->screen_lock_ms()) &&
-      lock_ms < delays->idle_ms())
+      lock_ms < delays->idle_ms()) {
     delays->set_screen_lock_ms(lock_ms);
+  }
 
   delays = prefs_policy_.mutable_battery_delays();
   delays->set_screen_dim_ms(values.battery_screen_dim_delay_ms);
@@ -170,8 +171,9 @@ void PowerPolicyController::ApplyPrefs(const PrefValues& values) {
   lock_ms = delays->screen_off_ms() + kScreenLockAfterOffDelayMs;
   if (values.enable_screen_lock && delays->screen_off_ms() > 0 &&
       (delays->screen_lock_ms() <= 0 || lock_ms < delays->screen_lock_ms()) &&
-      lock_ms < delays->idle_ms())
+      lock_ms < delays->idle_ms()) {
     delays->set_screen_lock_ms(lock_ms);
+  }
 
   prefs_policy_.set_ac_idle_action(GetProtoAction(values.ac_idle_action));
   prefs_policy_.set_battery_idle_action(
@@ -190,6 +192,13 @@ void PowerPolicyController::ApplyPrefs(const PrefValues& values) {
   SendCurrentPolicy();
 }
 
+void PowerPolicyController::ClearPrefs() {
+  prefs_policy_.Clear();
+  honor_screen_wake_locks_ = true;
+  prefs_were_set_ = false;
+  SendCurrentPolicy();
+}
+
 int PowerPolicyController::AddScreenWakeLock(const std::string& reason) {
   int id = next_wake_lock_id_++;
   screen_wake_locks_[id] = reason;