Bug 1016148 - Rename WMFOutputSource and friends to MFTManager, since it now handles input as well as output. r=padenot

--HG--
rename : content/media/fmp4/wmf/WMFAudioOutputSource.cpp => content/media/fmp4/wmf/WMFAudioMFTManager.cpp
rename : content/media/fmp4/wmf/WMFAudioOutputSource.h => content/media/fmp4/wmf/WMFAudioMFTManager.h
rename : content/media/fmp4/wmf/WMFVideoOutputSource.cpp => content/media/fmp4/wmf/WMFVideoMFTManager.cpp
rename : content/media/fmp4/wmf/WMFVideoOutputSource.h => content/media/fmp4/wmf/WMFVideoMFTManager.h
Bug 1016148 - Ensure we mark IMFSamples after a flush as discontinuities, so that A/V sync works after seek in MP4Reader. r=padenot