== Motivation
Mute a log channel, for which the Logger object is injected by
service wiring, for a service that is overridden by default,
such as 'DBLoadBalancerFactory'. For that, calling setLogger()
mid-test would be too late.
== Changes
* Add a test-only method to LegacyLogger that makes it possible
to change its `minimumLevel` attribute, thus making it turn
itself into a NullLogger if raised to infinity. This is the
same principle we use already for disabled log channels when
using MediaWiki normally (see LegacyLogger::__construct).
* Previously, the developer's LocalSettings.php was loaded
which includes the Spi configuration. This meant other Spi's
could be configured which means we might not be dealing with
a LegacyLogger object.
Similar to what we do with ObjectCache and JobQueue already,
make the default Spi in tests the same as the normal MW default.
* Add setNullLogger() which makes use of these two.
Bug: T248195
Change-Id: Ieade3585812de47342259afa765e230fff06f526
e0ed6df864