[lockscreen] Improve the default sizes of media toolbuttons and LockScreen.qml
[lockscreen] Set a default width and height
- This makes it start with a sane default size when run with qmlscene
[lockscreen] Increase the size of next/previous media toolbuttons
- I didn't think there was enough padding around the buttons here
Before:
After:
Do not squash
cc: @teams/vdg