Handle different types of streams in different jpeg source managers

For streams that are memory backed (stream->getMemoryBase() returns
a non-null ptr and hasLength() returns true), handle the stream
with skjpeg_mem_source_mgr, which directly assigns memory base to
the source manager.  For other non memory backed streams, handle the
stream with skjpeg_buffered_source_mgr, which is renamed from
the old skjpeg_source_mgr with no implementation change.

Signed-off-by: cjbao <cathy.bao@intel.com>
Bug: skia:
Change-Id: I748de0bdba726bbb318922c08497135e73e37329
Reviewed-on: https://skia-review.googlesource.com/17296
Reviewed-by: Leon Scroggins <scroggo@google.com>
Reviewed-by: Matt Sarett <msarett@google.com>
Commit-Queue: Matt Sarett <msarett@google.com>
4 files changed