I177dad88 introduced the skin version user preference field and
associated configuration values. Per T242381, the field is to presented
as a checkbox with the implied storage type of a boolean where a string
is needed. A PreferencesFormPreSave hook handler was added to adapt
values of either data type to the other. While this was a neat solution
to a minor nit, the adapter's implementation is incompatible with the
GlobalPreferences extension as the PreferencesFormPreSave hook isn't run
whilst saving global preferences.
Rather than adding an equivalent hook to the GlobalPreferences
extension, create a custom field based on a checkbox with the adapter
included. This allows us to:
- Separate the business logic concerned with preserving the user's
VectorSkinVersion preference if they've simply disabled Vector from
the adapter
- Simplify the adapter's implementation
- Forego adding hooks to the GlobalPreferences codebase
Additional changes:
- Replace repeated string literals with equivalent constants in
tests/phpunit/integration/VectorHooksTest.php
Bug: T258493
Change-Id: I628435a4ad676f55534191b8c10147be28be5d73
