Subtle fix when queue becomes unrunnable.

When broadcasts are skipped or failed during list traversal, we might
encounter a queue that is no longer runnable; skip it.

Also add new mPendingUrgent contents to dumpsys output.

Bug: 253906105
Test: atest FrameworksMockingServicesTests:BroadcastRecordTest
Test: atest FrameworksMockingServicesTests:BroadcastQueueTest
Test: atest FrameworksMockingServicesTests:BroadcastQueueModernImplTest
Change-Id: Ib85f3f33a9475cd4cd35f04afbc548e386b75c60