Move webrtc/audio_*.h to webrtc/api/call

BUG=webrtc:5878
NOTRY=True

Review-Url: https://codereview.webrtc.org/2059703002
Cr-Commit-Position: refs/heads/master@{#13996}

webrtc/api/api.gyp

@@ -94,10 +94,27 @@
     }],
   ],  # conditions
   'targets': [
+    {
+      'target_name': 'call_api',
+      'type': 'static_library',
+      'dependencies': [
+        # TODO(kjellander): Add remaining dependencies when webrtc:4243 is done.
+        '<(webrtc_root)/base/base.gyp:rtc_base_approved',
+        '<(webrtc_root)/common.gyp:webrtc_common',
+        '<(webrtc_root)/modules/modules.gyp:audio_encoder_interface',
+      ],
+      'sources': [
+        'call/audio_receive_stream.h',
+        'call/audio_send_stream.h',
+        'call/audio_sink.h',
+        'call/audio_state.h',
+      ],
+    },
     {
       'target_name': 'libjingle_peerconnection',
       'type': 'static_library',
       'dependencies': [
+        ':call_api',
         '<(webrtc_root)/media/media.gyp:rtc_media',
         '<(webrtc_root)/pc/pc.gyp:rtc_pc',
       ],