GitLab

Instead of just clearing the canvas when going out of view, remove it.
Recreate the canvas once needed again.

Bug: 1134057
Change-Id: I11131d7bf584eb51c94f4fd24484ba9f6675e75e
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2451387Reviewed-by: dpapad <dpapad@chromium.org>
Reviewed-by: Rebekah Potter <rbpotter@chromium.org>
Commit-Queue: Daniel Hosseinian <dhoss@chromium.org>
Cr-Commit-Position: refs/heads/master@{#814803}