[Harmony Cast Dialog] Explicitly remove issues

Clear issues shown in the Views dialog by sending explicit ClearIssue()
calls, instead of doing so by sending invalid CreateRoute() requests.

Bug: 923172
Change-Id: I79edc224505fec1debc06d782d1fda0acd6ccaf3
Reviewed-on: https://chromium-review.googlesource.com/c/1419201
Commit-Queue: Takumi Fujimoto <takumif@chromium.org>
Reviewed-by: mark a. foltz <mfoltz@chromium.org>
Cr-Commit-Position: refs/heads/master@{#624896}
5 files changed