* Changed Segmenters to accept StreamInfo rather than MediaStream
to help in testing.
* Changed MemoryFile behavior to mirror local file:
* Read non-existent file is an error.
* Write deletes any existing file.
* Fixed a bug in SingleSegmentSegmenter.
Change-Id: I339e35597ca4661b7a26c6fdbbfa2f9f511c7da0
This can be used for unit tests to reduce the need for temporary
files. A MemoryFile acts the same as any other File object, but
stores the contents in memory. The memory pointer can be accessed
directly. A file with the 'memory://' prefix will be a memory file.
Change-Id: I10ae3ed5391c8fd838e6dfb33106dec959bdc224