Implement a working MPRIS DBus connection with a separate API to control it. Right now only player playback state is reflected and Play/Pause/PlayPause calls work.
Controls panel height is now 3px less then before (as intended). Change default window size setting to make it look good with 16:9 video on fresh install.
Player window is considered mobile friendly with its transitions and touch/swipes gestures implemented. The only missing part now is preferences window that needs moving to libadwaita. Due to video playback being mobile friendly, mark this app as Purism Mobile compatible which will allow the app to appear on mobile app store and show the app icon in app launcher.
I were never able to get setifactionary results with this because:
* In GTK apps new window is created from the same process
* OpenGL is single-threaded so performance per window is halfed
* GTK4 has problems with rendeing using multiple contexts resulting in some frames being upside down
So for the time being I am removing a non-working option. There is a chance
that it will be fixed and added in future, but for now lets not
advertise a functionality that does not work.
We cannot depend on the value saved by GStreamer, cause it is shared with all GStreamer based apps. Lets save the last value to gsettings instead to make sure this is the volume we used with this app. With this change we can also see the right volume on startup before media file is loaded (previously it was shown always as muted).
When dark theme is used, sliders (especially progress on fullscreen) tend to look a little too dark (as if they were disabled). To overcome this, add an option to force them to be 20% brighter.
The "vah264dec" plugin is a new and much better VAAPI implementation then default one in gstreamer-vaapi. Unfortunately as of now it works correctly only on Wayland and causes crashes on XOrg. Wayland users can easily enable it in video player preferences advanced tab settings to get improved performance and lower CPU usage.