ShadowLooper -> ShadowLegacyLooper
ShadowRealisticLooper -> ShadowPausedLooper
ShadowBaseLooper -> ShadowLooper
And all public methods from ShadowLegacyLooper get pushed up to ShadowLooper
Pull Request: https://github.com/robolectric/robolectric/pull/4868
Copybara: OK
Also adjust Google3 tests using custom looper shadows where necessary.
Convert exoplayer to paused looper to eliminate reliance on custom shadows
PiperOrigin-RevId: 243839311
