[automerger skipped] Merge "Fix bidirectional sequence RNN crash when auxiliary input is omitted" am: 05bffb5fcd am: 4769062b79 -s ours am: 373d233a1c -s ours
am: c9715d4425 -s ours
am skip reason: change_id I47168d6a59445d2591a3c25ce7bbd4e17e6b2547 with SHA1 66ac071171 is in history

Change-Id: I86da4f1b2e1b54ec2618e93413348c4ceb24590c