[DO NOT MERGE] Reset mTrackingReportedValues in endSample()

Otherwise, when next SamplingTimer.update() is called, it will take
zero as start time.

Bug: 142466892
Test: NA.

Change-Id: I04625fadd8fd8bab3ba83b8e7cd10737ad34e60b
(cherry picked from commit c7d49e01dd)

core/java/com/android/internal/os/BatteryStatsImpl.java

@@ -1868,6 +1868,7 @@ public class BatteryStatsImpl extends BatteryStats {
             mCount = computeCurrentCountLocked();
             mUnpluggedReportedTotalTime = mCurrentReportedTotalTime = 0;
             mUnpluggedReportedCount = mCurrentReportedCount = 0;
+            mTrackingReportedValues = false;
         }
 
         public void setUpdateVersion(int version) {