520f8a9e23 extracted gerrit-gwtui-common
from gerrit-gwtui to make it possible to reuse the common UI code from
Gerrit core and plugins.
gerrit_plugin() rule wasn't adjusted to respect the new dependency for
Gerrit plugins that expose GWT modules.
Change-Id: I595b10ac313dabd7776b0ee25ea5b5939ef3e063