Move remaining traces of VoiceEngine

- Move files from voice_engine/ to audio/.
- Rename voice_engine/utility.* to remix_resample.* since there are no other
  utilities in those files.
- Move test/mock_voe_channel_proxy.h to audio/.
- Removed voe_channel_id from Audio[Receive|Send]Stream::Config.
- Remove VoiceEngine* from AudioState::Config.
- Fix a few cpplint complaints which showed when moving files.

NOPRESUBMIT=true

Bug: webrtc:4690
Change-Id: Id266c822d956625c358fa5e193e6f4837164aef8
Reviewed-on: https://webrtc-review.googlesource.com/39268
Commit-Queue: Fredrik Solenberg <solenberg@webrtc.org>
Reviewed-by: Karl Wiberg <kwiberg@webrtc.org>
Cr-Commit-Position: refs/heads/master@{#21657}
diff --git a/WATCHLISTS b/WATCHLISTS
index ed0a614..b6a5703 100644
--- a/WATCHLISTS
+++ b/WATCHLISTS
@@ -23,8 +23,7 @@
       'filepath': '^[^/]*$|^webrtc/[^/]*$|^webrtc/build/.*',
     },
     'documented_interfaces': {
-      'filepath': '^webrtc/[^/]*\.h$|'\
-                  'webrtc/voice_engine/include/.*',
+      'filepath': '^webrtc/[^/]*\.h$',
     },
     'build_files': {
       'filepath': '\.gyp$|\.gypi$|Android\.mk$',
@@ -50,9 +49,6 @@
     'video': {
       'filepath': 'webrtc/video/.*',
     },
-    'voice_engine': {
-      'filepath': 'webrtc/voice_engine/.*',
-    },
     'common_audio': {
       'filepath': 'webrtc/common_audio/.*',
     },
@@ -126,20 +122,11 @@
     'call': ['mflodman@webrtc.org',
              'solenberg@webrtc.org',
              'stefan@webrtc.org'],
-    'media_engine': ['solenberg@webrtc.org'],
     'video': ['mflodman@webrtc.org',
               'stefan@webrtc.org',
               'video-team@agora.io',
               'yujie.mao@webrtc.org',
               'zhengzhonghou@agora.io'],
-    'voice_engine': ['alessiob@webrtc.org',
-                     'andrew@webrtc.org',
-                     'audio-team@agora.io',
-                     'henrika@webrtc.org',
-                     'henrik.lundin@webrtc.org',
-                     'minyue@webrtc.org',
-                     'peah@webrtc.org',
-                     'solenberg@webrtc.org'],
     'video_capture': ['mflodman@webrtc.org',
                       'perkj@webrtc.org',
                       'sdk-team@agora.io',