Fix system watchdog timeout when reading too many usage events.

Symptom:
As issue link:
https://code.google.com/p/android/issues/detail?id=193100

RootCause:
UsageStatsService.onDisplayChanged executed in system main thread,
If calling UsageStatsManager.queryEvents with too many events before it
(i.e. in daily usage event file,
too many activity resume / pause events or configuration change
during monkey test),
System will be blocked then watchdog timeout.

Solution:
Let display listener executed in background thread handler

BUG: 25355086

Change-Id: Ic894d112612400ed8fb7ba843b3309fdc4f66fe1
(Cherrypicked from 4e59db328d8b0cc163d2e3eb0f7f3a108f20a58d)
(cherry picked from commit 7018f60b06fd0c647ebf13225320d7e15d02e075)

1 files changed, 1 insertions, 1 deletions

diff --git a/services/usage/java/com/android/server/usage/UsageStatsService.java b/services/usage/java/com/android/server/usage/UsageStatsService.java
index 2b8afba..54d9cd9 100644
--- a/services/usage/java/com/android/server/usage/UsageStatsService.java
+++ b/services/usage/java/com/android/server/usage/UsageStatsService.java
@@ -218,7 +218,7 @@ public class UsageStatsService extends SystemService implements
             synchronized (this) {
                 mScreenOnTime = readScreenOnTimeLocked();
             }
-            mDisplayManager.registerDisplayListener(mDisplayListener, null);
+            mDisplayManager.registerDisplayListener(mDisplayListener, mHandler);
             synchronized (this) {
                 updateDisplayLocked();
             }