Improve Magnifier error messages

[CyrilleB79]

Link to issue number:

None

Summary of the issue:

When trying to execute Magnifier commands while Magnifier is not active, there is no error message and an error is logged because pgettext context argument has been put at a wrong position.

Description of user facing changes:

• Executing Magnifier commands when Magnifier is not active now report a message as expected.
• The reported messages have been improved to be more similar to other NVDA messages when an action cannot be performed.

Description of developer facing changes:

N/A

Description of development approach:

• Fix pgettext call
• Reworded error messages

Testing strategy:

Manuel tests of all Magnifier commands.

The full screen scheck has not been tested since for now, no other mode is available.

Known issues with pull request:

N/A

Code Review Checklist:

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

[CyrilleB79]

@Boumtchack feel free to comment here.

[CyrilleB79]

Test failure is unrelated.

[Boumtchack]

I've added more gestures regarding to padding so I guess it'll add up to what you wanted to change.

I think I'll adapt my code to what you are doing here if it's validated

[seanbudd]

Thanks @CyrilleB79 these changes look good to me