Bug 1404977 - Part 6 - Remove unused include for lock-free FIFO. r=pehrsons

MozReview-Commit-ID: 8gVKlD7lMIX

--HG--
extra : rebase_source : cc5e02d3acb3a46edafe58002ff8e4d1e974b235

dom/media/webrtc/MediaEngineWebRTCAudio.cpp

@@ -23,7 +23,6 @@
 #ifdef FF
 #undef FF
 #endif
-#include "webrtc/modules/audio_device/opensl/single_rw_fifo.h"
 #include "webrtc/voice_engine/voice_engine_defines.h"
 #include "webrtc/modules/audio_processing/include/audio_processing.h"
 #include "webrtc/common_audio/include/audio_util.h"