hterm: terminal: use local color state when processing reverse video
hterm: terminal: use local color state when processing reverse video

The terminal initializes its fg/bg colors from the user prefs, but
after that, can be changed to other values on the fly without the
user prefs changing.  When we need the fg/bg colors later on, we
should load from the terminal object state rather than reaching
back into the user prefs.  Otherwise, temporal changes made to
the object will be reset when processing reverse video.

Change-Id: I9aa121f85de129e54c5b3a7e0e19fd7d99219def
Reviewed-on: https://chromium-review.googlesource.com/c/apps/libapps/+/1711497
Reviewed-by: Joel Hockey <9ecfc52dc2ffef73afac73f3495f294aeddf1231@chromium.org>
Tested-by: Mike Frysinger <8f3f75c74bd5184edcfa6534cab3c13a00a2f794@chromium.org>

chromium/hterm,chromium/hterm,chromium/hterm,chromium/hterm