Allows continues persist snapshots to disk via ImageReader

Via creating Bitmap object via ImageReader, there won't take graphic
resources when persist snapshots to disk, so it won't slow down the
refresh rate anymore.
Second, when adding an item to mWriteQueue, remove any mutually
exclusive action items. When inserting a delete item, remove the
corresponding store item (and vice versa), as the previous action will
eventually be overridden.
Update the limitation for store queue depth:
- Hardware render involved items < MAX_HW_STORE_QUEUE_DEPTH
- Total (SW + HW) items < MaxRecentTasks

Flag: com.android.window.flags.extending_persistence_snapshot_queue_depth
Bug: 416144425
Test: atest TaskSnapshotPersisterLoaderTest ActivitySnapshotControllerTests
Test: swipe up to close desktop mode tasks, verify task snapshots can
persist in disk.
Test: run DisplayRefreshRateTest#testRefreshRate right after above
step, verify refresh rate won't drop down.

Change-Id: I0c370b63eed22007229fa26d695a31a93aef8acc