Attempt to fix bubbles gesture pilfering

1. Remove bubble gesture monitor immediately when collapsing
2. Verify we're still attached when continuing to collapse
   after the IME was hidden; log if we're detached
3. Clear the IME hidden runnable when removing views from window
   manager

Fixes: 424528947
Bug: 423052244
Flag: EXEMPT bug fix
Test: manual -- this is hard to repro so just test normal behavior
       - verify that IME and bubbles functionality works
       - verify swipe up gesture works when bubbles expanded and
         collapsed
Change-Id: Icdfab0631c1197cb941ad5fc69d59ff855a4e2ad