Chameleon: Catch the wrong resolution earlier

Calling wait_video_input_stable before doing screen comparison helps
catching issues earlier.

BUG=chromium:446233
TEST=Ran display_ResolutionList on peach_pi.

Change-Id: Ia7893df417214f82892b4c3b2c6e00db934d2376
Reviewed-on: https://chromium-review.googlesource.com/241174
Tested-by: Wai-Hong Tam <waihong@chromium.org>
Reviewed-by: Hung-ying Tyan <tyanh@chromium.org>
Commit-Queue: Wai-Hong Tam <waihong@chromium.org>
1 file changed