Allow easy gmerge overrides for board and devserver_url.

Right now, we only use what's in /etc/lsb-release for gmerge
settings. This is fine for a developer, but now with dev_install
fixed in R27, gmerge has become very useful for devs in dev mode.

The /usr/local override specifically has been long wanted.

Also did a little refactoring and fixed some pylint warnings.

TEST=Ran it on a stumpy Chrome OS machine after dev_install and using
local workstation to build and install screen w/without options.

Change-Id: Ie1bac164bc8a2e3028bfa449bdbeba85e8bec66a
(cherry picked from commit 6c92214d04e0558cd415a78a3ee33e4823ded02b)
Reviewed-by: Chris Sosa <>
Tested-by: Chris Sosa <>
2 files changed