[Touchless] Add instructions to the dino page

Please refer to the bug for screenshots.

Bug: 957992
Change-Id: I933b599df2f4862cca4a62aaff96d455f1ea9675
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1674747
Reviewed-by: Ted Choc <tedchoc@chromium.org>
Reviewed-by: Cathy Li <chili@chromium.org>
Commit-Queue: Mehran Mahmoudi <mahmoudi@chromium.org>
Cr-Commit-Position: refs/heads/master@{#672278}
5 files changed