GitLab

This CL adds a method to explicitly close the virtual keyboard.
It will be used from Tast's Chrome ResetState function.

Tast side CL: https://crrev.com/c/2071552

TEST=tast run arc.ChromeVirtualKeyboard
BUG=None

Change-Id: Iffb9fb1f9b9e5059b38d3315f9d135d23624a479
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2071549
Commit-Queue: Tetsui Ohkubo <tetsui@chromium.org>
Reviewed-by: Toni Baržić <tbarzic@chromium.org>
Reviewed-by: Keith Lee <keithlee@chromium.org>
Reviewed-by: Darren Shen <shend@chromium.org>
Cr-Commit-Position: refs/heads/master@{#746227}