Protect against multiple starts of device index job

Its rare, but can happen.

Test: existing tests pass
Change-Id: Ie7aaa47902741d5f7fdd954f35e8f13e9466e07c
Fixes: 78898947

src/com/android/settings/search/DeviceIndexUpdateJobService.java

@@ -53,10 +53,12 @@ public class DeviceIndexUpdateJobService extends JobService {
     @Override
     public boolean onStartJob(JobParameters params) {
         if (DEBUG) Log.d(TAG, "onStartJob");
+        if (!mRunningJob) {
             mRunningJob = true;
             Thread thread = new Thread(() -> updateIndex(params));
             thread.setPriority(Thread.MIN_PRIORITY);
             thread.start();
+        }
         return true;
     }