Chameleon: Make ChameleonPortFinder work on both client and server tests

This change is to demonstrate how a library, like ChameleonPortFinder, work
on both client and server tests. The interfaces to access DUT audio/display
are achieved by the facade, either locally or remotely.

It also makes all client and server Chameleon tests use ChameleonPortFinder
to identity the connected ports.

BUG=chromium:405143
TEST=Ran the chameleon_hdmi suite and verified it did not break the tests.

Change-Id: I9f991296eb497e2e86655635bc433618d4b45a5c
Reviewed-on: https://chromium-review.googlesource.com/226142
Reviewed-by: Wai-Hong Tam <waihong@chromium.org>
Tested-by: Wai-Hong Tam <waihong@chromium.org>
Commit-Queue: Wai-Hong Tam <waihong@chromium.org>
4 files changed