GitLab

Before this change, consecutive showcasts with identical element areas
did not work unless the user somehow changed the area (e.g., scrolling).
This was because the last showcasted viewport and element was cached and
not properly reset.

Bug: b/161471176
Change-Id: I746cd365c2b1bcdf2fcf7271cbc7666d83bea0c5
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2306096Reviewed-by: Marian Fechete <marianfe@google.com>
Reviewed-by: Mathias Carlen <mcarlen@chromium.org>
Commit-Queue: Clemens Arbesser <arbesser@google.com>
Cr-Commit-Position: refs/heads/master@{#790288}