[Mfill Android] Ensure hiding the sheet trigggers relayouting

When a keyboard disappears, the compositor waits for a relayout as a
signal to proceed with a closed keyboard.

With https://crrev.com/c/1503574, this was removed and caused tasks that
were deferred to be executed when the next relayouting happened - see
linked bug for an example.

Bug: 954125
Change-Id: I925cb2b0f4e6fab7158bf7eb16348116e5c09b1d
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1578611
Reviewed-by: Ioana Pandele <ioanap@chromium.org>
Commit-Queue: Friedrich [CET] <fhorschig@chromium.org>
Cr-Commit-Position: refs/heads/master@{#653174}
2 files changed