Add a script to cycle through language switching modes. (#13680)
Fixes #10253
Summary of the issue:
A gesture is missing to control automatic language switching and automatic dialect switching options.
Description of how this pull request fixes the issue:
Add an unassigned script that cycles through the 3 following automatic language and dialect switching modes:
- Language and dialect switching off
- Language switching on, dialect switching off
- Language and dialect switching on
Note that the 4th possible state (language switching off and dialect switching on) does not make sense.
