Don't allow strong view handles to be read/updated with an AsyncAppContext

This avoids an invitation to hold strong view handles across async await
points, which is a common source of leaks.

Co-Authored-By: Nathan Sobo <nathan@zed.dev>
6317e885c7Antonio Scandurra committed on 4/26/2023, 11:36:13 AMparent689e878
14 files changedLine totals unavailable