Make reprocess mechanism support multi-cameras

This CL makes reprocess mechanism support multi-cameras by translating
source id to video device id at runtime.

Bug: b/117817062
Test: None
Change-Id: I9e0422ecf2d0ceeeb8dcd943c01638e48ae4f79c
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1424680
Commit-Queue: Wei Lee <wtlee@chromium.org>
Reviewed-by: Ricky Liang <jcliang@chromium.org>
Reviewed-by: Christian Fremerey <chfremer@chromium.org>
Reviewed-by: Robert Sesek <rsesek@chromium.org>
Reviewed-by: Ken Rockot <rockot@google.com>
Cr-Commit-Position: refs/heads/master@{#642841}
12 files changed