This will give an app an opportunity to learn whether an input port is busy
before the user tries to connect and then fails.
Bug: 22825043
Change-Id: Ifede60f166dfe66ea15453044fce06f4a8452b18
Signed-off-by: Phil Burk <philburk@google.com>
(cherry picked from commit b2355940e3e697deeecd1b6511cd5094f9dc553a)