b=920987 check for ovrflw in addition r=ehsan

--HG--
extra : rebase_source : 759d416f4697bb60dd24b104678b6fb259ee308d
b=912474 use speex_resampler_process_int on platforms where speex_resampler_process_float expects samples in the range +/-32767 r=ehsan

--HG--
extra : rebase_source : 48b08dc174e49d26b80ac4e439f97c5e2fa65f58