/usr/include/webrtc_audio_processing/webrtc/ is in libwebrtc-audio-processing-dev 0.3-1.
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..
/usr/include/webrtc_audio_processing/webrtc/base/
/usr/include/webrtc_audio_processing/webrtc/base/arraysize.h
/usr/include/webrtc_audio_processing/webrtc/base/basictypes.h
/usr/include/webrtc_audio_processing/webrtc/base/checks.h
/usr/include/webrtc_audio_processing/webrtc/base/constructormagic.h
/usr/include/webrtc_audio_processing/webrtc/base/maybe.h
/usr/include/webrtc_audio_processing/webrtc/base/platform_file.h
/usr/include/webrtc_audio_processing/webrtc/common.h
/usr/include/webrtc_audio_processing/webrtc/common_types.h
/usr/include/webrtc_audio_processing/webrtc/modules/
/usr/include/webrtc_audio_processing/webrtc/modules/audio_processing/
/usr/include/webrtc_audio_processing/webrtc/modules/audio_processing/beamformer/
/usr/include/webrtc_audio_processing/webrtc/modules/audio_processing/beamformer/array_util.h
/usr/include/webrtc_audio_processing/webrtc/modules/audio_processing/include/
/usr/include/webrtc_audio_processing/webrtc/modules/audio_processing/include/audio_processing.h
/usr/include/webrtc_audio_processing/webrtc/modules/interface/
/usr/include/webrtc_audio_processing/webrtc/modules/interface/module_common_types.h
/usr/include/webrtc_audio_processing/webrtc/system_wrappers/
/usr/include/webrtc_audio_processing/webrtc/system_wrappers/include/
/usr/include/webrtc_audio_processing/webrtc/system_wrappers/include/trace.h
/usr/include/webrtc_audio_processing/webrtc/typedefs.h