Revert of Revert of chromeos: Don't send empty power management policies.

chromeos/dbus/power_policy_controller.h

Index: chromeos/dbus/power_policy_controller.h
diff --git a/chromeos/dbus/power_policy_controller.h b/chromeos/dbus/power_policy_controller.h
index 7db9091af22f87eb610ffc95965306a70314aecb..cb994cdb830a1fb71c73cbcf8c0566db7a1644f5 100644
--- a/chromeos/dbus/power_policy_controller.h
+++ b/chromeos/dbus/power_policy_controller.h
@@ -11,7 +11,6 @@
 #include "base/basictypes.h"
 #include "base/compiler_specific.h"
 #include "chromeos/chromeos_export.h"
-#include "chromeos/dbus/dbus_thread_manager_observer.h"
 #include "chromeos/dbus/power_manager/policy.pb.h"
 #include "chromeos/dbus/power_manager_client.h"
 
@@ -22,8 +21,7 @@
 // PowerPolicyController is responsible for sending Chrome's assorted power
 // management preferences to the Chrome OS power manager.
 class CHROMEOS_EXPORT PowerPolicyController
-    : public DBusThreadManagerObserver,
-      public PowerManagerClient::Observer {
+    : public PowerManagerClient::Observer {
  public:
   // Note: Do not change these values; they are used by preferences.
   enum Action {
@@ -79,9 +77,6 @@
   // Updates |prefs_policy_| with |values| and sends an updated policy.
   void ApplyPrefs(const PrefValues& values);
 
-  // Resets |prefs_policy_| to its defaults and sends an updated policy.
-  void ClearPrefs();
-
   // Registers a request to temporarily prevent the screen from getting
   // dimmed or turned off or the system from suspending in response to user
   // inactivity and sends an updated policy.  |reason| is a human-readable
@@ -94,10 +89,6 @@
   // AddSystemWakeLock() and sends an updated policy.
   void RemoveWakeLock(int id);
 
-  // DBusThreadManagerObserver implementation:
-  virtual void OnDBusThreadManagerDestroying(DBusThreadManager* manager)
-      OVERRIDE;
-
   // PowerManagerClient::Observer implementation:
   virtual void PowerManagerRestarted() OVERRIDE;
 
@@ -109,11 +100,7 @@
   // Sends a policy based on |prefs_policy_| to the power manager.
   void SendCurrentPolicy();
 
-  // Sends an empty policy to the power manager to reset its configuration.
-  void SendEmptyPolicy();
-
-  DBusThreadManager* manager_;  // not owned
-  PowerManagerClient* client_;  // not owned
+  PowerManagerClient* client_;  // weak
 
   // Policy derived from values passed to ApplyPrefs().
   power_manager::PowerManagementPolicy prefs_policy_;