Fix Wifi Aware session check.

We should skip the creation if the future is complete but
not exceptionally.

The current check is for "is future not complete exceptionally",
which is true in the beginning and the session is never attached.

Bug: n/a
Test: manual
Change-Id: I4a0d0b87930cf0f0f42b33a652b92e9fe7cafa82
1 file changed