audio: Fix CRAS bug (hanging cras_test_client)

Introduced in upstream build 5339, fixed in build 5579, see http://crbug.com/347997 . Patching until we know if upstream wants to include it in R34-5500.

Tested in `2014-03-11_02-03-14_drinkcat_chroagh_audio-fix-5500_-R_precise_30`. Only issue is that only stable and dev have been tested on ARM (builds 5116 and 5579), which are not affected by the bug (current beta is: build 5500).