SystemUI: Make mBatteryDead accessible in subclasses

Change-Id: I26b2fce45dd5f0cb7e77e8b7cd2eb943b1c5702e

Author: ralph950412

packages/SystemUI/src/com/android/systemui/statusbar/KeyguardIndicationController.java

@@ -223,7 +223,7 @@ public class KeyguardIndicationController {
     private boolean mBatteryDefender;
     /** Whether the battery defender is triggered with the device plugged. */
     private boolean mEnableBatteryDefender;
-    private boolean mBatteryDead;
+    protected boolean mBatteryDead;
     private boolean mIncompatibleCharger;
     private int mChargingWattage;
     private int mBatteryLevel = -1;