Fix lock contention while swiping up

- Don't lock when making WM calls (only lock when resetting), and use own
  executor since the background executor is fixed to only two threads and
  other things can be running on them already (like task loading).

Bug: 78585335

Change-Id: I73dfc380dd99908cfc30ff7c164a9677a5a126e0
2 files changed