Add an API for apps to get their System Health / Battery Stats data.

Change-Id: Ib27e1be469b826f6d83d73ce6024102bbdb1d47a
diff --git a/core/java/android/os/BatteryStats.java b/core/java/android/os/BatteryStats.java
index 8281279..e1c7ad77 100644
--- a/core/java/android/os/BatteryStats.java
+++ b/core/java/android/os/BatteryStats.java
@@ -465,6 +465,7 @@
         };
 
         public abstract long getProcessStateTime(int state, long elapsedRealtimeUs, int which);
+        public abstract Timer getProcessStateTimer(int state);
 
         public abstract Timer getVibratorOnTimer();