Implements pre shared key in P2PQuicTransport.

A few small changes to implement the pre shared key with the
P2PQuicTransportImpl. This includes updating so that the crypto streams
aren't created at construction time, adding a setter and removing the
splitting out the default setter for the remote fingerprints.

Bug: 874296
Change-Id: I76be13eb90365b6f75edf4c3951c49fe4cce2ef3
Commit-Queue: Seth Hampson <>
Reviewed-by: Steve Anton <>
Cr-Commit-Position: refs/heads/master@{#623788}
7 files changed