Normal binaries should never have to do this. It's not safe when there are
already some goroutines running which might do logging. Therefore the new
default is to return an error when a binary accidentally re-applies.
A few unit ensure that there are no goroutines and have to call the functions
more then once. The new ResetForTest API gets used by those to enable changing the
logging settings more than once in the same process.
Integration tests use the same code as the normal binaries. To make reuse of
that code safe, component-base/logs can be configured to silently ignore any
additional calls. This addresses data races that were found when enabling -race
for integration tests. To catch cases where the integration test does want
to modify the config, the old and new config get compared and an error is
raised when it's not the same.
To avoid having to modify all integration tests which start test servers,
reconfiguring component-base/logs is done by the test server packages.
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