DO NOT MERGE ANYWHERE: Don't change screen on time on time changes

Screen on time should be measured in elapsed realtime, not wallclock.

Cause a checkIdleStates to occur when reloading stats
(on rollover and on time change).

When time changes occur in the negative direction, the new stats file
we create can overlap the previous one with regards to its end timestamp.
Use the begin timestamp to determine which of the latest stats to merge.
(b/22716352)

Bug: 26488100
Change-Id: If31b29bbbee9e98401205b5e26bce86e181286e7

1 files changed, 6 insertions, 2 deletions

diff --git a/core/java/android/app/usage/UsageStats.java b/core/java/android/app/usage/UsageStats.java
index 0fce4e2..a88aa31 100644
--- a/core/java/android/app/usage/UsageStats.java
+++ b/core/java/android/app/usage/UsageStats.java
@@ -165,14 +165,18 @@ public final class UsageStats implements Parcelable {
                     mPackageName + "' with UsageStats for package '" + right.mPackageName + "'.");
         }
 
-        if (right.mEndTimeStamp > mEndTimeStamp) {
+        if (right.mBeginTimeStamp > mBeginTimeStamp) {
+            // The incoming UsageStat begins after this one, so use its last time used fields
+            // as the source of truth.
+            // We use the mBeginTimeStamp due to a bug where UsageStats files can overlap with
+            // regards to their mEndTimeStamp.
             mLastEvent = right.mLastEvent;
-            mEndTimeStamp = right.mEndTimeStamp;
             mLastTimeUsed = right.mLastTimeUsed;
             mBeginIdleTime = right.mBeginIdleTime;
             mLastTimeSystemUsed = right.mLastTimeSystemUsed;
         }
         mBeginTimeStamp = Math.min(mBeginTimeStamp, right.mBeginTimeStamp);
+        mEndTimeStamp = Math.max(mEndTimeStamp, right.mEndTimeStamp);
         mTotalTimeInForeground += right.mTotalTimeInForeground;
         mLaunchCount += right.mLaunchCount;
     }