- Ensure that no memory is used by audio processors that are always inactive, by
only allocating in flush() if active. If data was already allocated but a
processor becomes inactive we assume that the allocation may be needed in
future so do not remove it (e.g., in the case of ResamplingAudioProcessor).
- Make SilenceSkippingAudioProcessor set up its buffers in flush(), and clarify
that it is always necessary to call flush() if configure() returns true.
- Make reset() reset all state for all processors.
- Use @Nullable state or empty arrays for inactive audio processor buffers.
- Miscellaneous style/consistency cleanup.
-------------
Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=190895783
This is not really useful with the DefaultAudioSink, but could be used in a
custom AudioSink when mixing audio from sources that have different sample
rates.
-------------
Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=172434482
