DO NOT MERGE ANYWHERE: Remove several memset() calls which overwrote buffers initialized in buf_mgr_init().  Affects 6.0 only. am: daefcde2ed  -s ours
am: 42f2d92bc4  -s ours

Change-Id: Ia22a55a7bcc1a684e1e357a0cb770188beb0d6fb