GNOME 48 support

[ChrisLauinger77]

https://gjs.guide/extensions/upgrading/gnome-shell-48.html is online as GNOME 48 beta is released.
It is working in my GnomeOS VM. 1 error is in log

[ChrisLauinger77]

Extension mediacontrols@cliffniff.github.com: TypeError: Mpris.MediaSection is undefined

Stack trace:
  updateMediaNotificationVisiblity@file:///home/christian/.local/share/gnome-shell/extensions/mediacontrols@cliffniff.github.com/extension.js:441:13
  enable@file:///home/christian/.local/share/gnome-shell/extensions/mediacontrols@cliffniff.github.com/extension.js:56:14
  _callExtensionEnable@resource:///org/gnome/shell/ui/extensionSystem.js:266:38
  loadExtension@resource:///org/gnome/shell/ui/extensionSystem.js:433:32
  async*_loadExtensions@resource:///org/gnome/shell/ui/extensionSystem.js:741:24
  async*_enableAllExtensions@resource:///org/gnome/shell/ui/extensionSystem.js:747:48
  _sessionUpdated@resource:///org/gnome/shell/ui/extensionSystem.js:782:20
  async*init@resource:///org/gnome/shell/ui/extensionSystem.js:76:14
  _initializeUI@resource:///org/gnome/shell/ui/main.js:329:22
  start@resource:///org/gnome/shell/ui/main.js:180:11
  @resource:///org/gnome/shell/ui/init.js:12:47
  @resource:///org/gnome/shell/ui/init.js:21:20
  

is what i currently get - nevertheless - it is working. i tested 5-10 minutes did not find anything

[ChrisLauinger77]

Found a commit - MediaSection was moved
https://gitlab.gnome.org/GNOME/gnome-shell/-/commit/0c6f896d4b69db1c121a68bfd3b88a56a1c86a25
With the latest GNOME 48 the extension does not gets enabled any more

[ChrisLauinger77]

I did some changes - I decided to break backward comp. in favour of cleaner code.
It works again - did not see any errors on start

[sakithb]

Looks good to me!