Merge "Add BidirectionalStreamCallback util class" am: f21c105b88

Original change: https://android-review.googlesource.com/c/platform/packages/modules/Connectivity/+/2460229

Change-Id: I1ea167050fb6e80d6c9c003a2b55d96fb6af07e3
Signed-off-by: Automerger Merge Worker <[email protected]>