Use common Comparator.

Every AlarmPriorityQueue will use the exact same comparator, so there's
no point creating a new one for each instance.

Bug: 247097209
Test: atest FrameworksMockingServicesTests:AlarmQueueTest
Change-Id: I8e07157fef57f6047414e9c8b46da0dac91c6714

services/core/java/com/android/server/utils/AlarmQueue.java

@@ -64,8 +64,11 @@ public abstract class AlarmQueue<K> implements AlarmManager.OnAlarmListener {
      * The pair is the key and its associated alarm time (in the elapsed realtime timebase).
      */
     private static class AlarmPriorityQueue<Q> extends PriorityQueue<Pair<Q, Long>> {
+        private static final Comparator<Pair<?, Long>> sTimeComparator =
+                (o1, o2) -> Long.compare(o1.second, o2.second);
+
         AlarmPriorityQueue() {
-            super(1, Comparator.comparingLong(o -> o.second));
+            super(1, sTimeComparator);
         }
 
         /**