tree f2b6fbebfc121f980593ced7e81dc7be3e5fea41
author Stephen Li <stephenli@google.com> 1467246965 -0700
committer Stephen Li <stephenli@google.com> 1478190154 -0700

Working prototype with tests.

When the plugin detects a patchset has been created, it will
merge downstream until it hits a merge conflict. On the
conflicting merge, it will vote -1 on a configurable label
and provide instructions to resolving the merge conflict.

Draft changes will be ignored until published.

The plugin will put all the auto-created changes in the
same topic as the original change (or create a topic if
none exists). If a user updates the topic, it will update
the topic of all the downstream merges.

If there are existing downstream merges from a previous
automerged patchset, it will update them all.

Admins can update the config.yaml file in tools/automerger
(this is configurable) in order to add merge paths and
do other configuration changes.

Javascript portion will add a button to optionally skip
or merge all downstream changes. It will also bold all
related changes in the same branch.

Change-Id: I89209ed29073f987a37d03e10dad85a1c5c530fb