SpeedChangingAudioProcessor is redundantly bypassing SonicAudioProcessor
when the speed is set to 1f. SpeedChangingAudioProcessor should not make
assumptions about the underlying audio processing and moreover should
not be bypassing any AudioProcessor based on parameter values. Default
parameter values are a valid state for an active AudioProcessor.
Sonic already handles the "default case" state by just copying the input
buffer onto the output buffer.
This CL also simplifies SonicAudioProcessor, which would mark itself as
inactive when configured with a valid set of default parameters. The API
contract for `isActive()` makes no mention about parameter state, which
makes changes in `isActive()` after applying new valid parameters quite
unintuitive.
PiperOrigin-RevId: 698000500