stagefright: httplive: Reduce memcpy calls for chunked content

Streams using http chunking will not report the segment's total
content-length. In this case, a 64k buffer is allocated and is
increased by 32k each time the buffer is filled again. For high
bitrate content, this can lead to a large number of copies that
affect the HLS framework delay. Increase fetchFile buffer size
exponentially by 50% or at least 32k instead of by 32k each time
to reduce the number of memcpy calls.

Example for a chunked 6 MB 1080p segment (ie ~3s):
Adding 32k:
190 copies with 572.97 MB copied

Increasing by 50%:
12 copies with 16.09 MB copied

CRs-Fixed: 745835
Change-Id: Iedf0e4437e96026a58d50bce2660f85ac90d0ada
Added support for YEAR metadata key from VorbisComments

The OggExtractor wasn't extracting the YEAR key when the metadata in
the file was parsed. The YEAR key is now extracted when the file
metadata is parsed.

Change-Id: Idf0d1a37fb141491dce5de527703ca1b27f621e7