Follow up for decide_enabled extension point

[LeonarddeR]

Link to issue number:

Fixup of #14503

Summary of the issue:

1. When a handler was registered to decide_enabled and a cursor was blinking or a message with timeout was shown on the braille display, the display would still be updated. Found when working on NVDA Remote to integrate the extension points.
2. The extensionPointTestHelpers wouldn't strictly test whether the handler was actually called. Also the handler argument for value was incorrect and using a class to store the filter value was overdone.

Description of user facing changes

When a handler decides to disable the braille handler, cursor blinking is now stopped and a message is dismissed.

Description of development approach

Pretty selfexplanatory.

Testing strategy:

Manual testing in the python console with a blinking cursor enabled:

f=lambda: False
braille.handler.decide_enabled.register(f)

Known issues with pull request:

None known

Change log entries:

None needed

Code Review Checklist:

• Pull Request description:
  • description is up to date
  • change log entries
• Testing:
  • Unit tests
  • System (end to end) tests
  • Manual testing
• API is compatible with existing add-ons.
• Documentation:
  • User Documentation
  • Developer / Technical Documentation
  • Context sensitive help for GUI changes
• UX of all users considered:
  • Speech
  • Braille
  • Low Vision
  • Different web browsers
  • Localization in other languages / culture than English
• Security precautions taken.