This commit fixes an issue where the following happens:
1. You open /admin as a member of the admin_sidebar_enabled_groups
1. You then click the chat icon in the header when you prefer to have
drawer open, or if you just minimise chat into drawer after it opens
fullscreen
1. You lose the admin sidebar panel, and are reset instead to the main
panel
Also included is a bit of refactoring to make it so the forcing of
admin sidebar state is in one place.
With the new admin sidebar restructure, we have a link to "Installed plugins". We would like to ensure that when the admin is searching for a plugin name like "akismet" or "automation" this link will be visible. Also when entering the plugins page, related plugins should be highlighted.
Martin Brennan
Krzysztof Kotlarek