Filter overlapping RTP header extensions.

talk/media/webrtc/webrtcmediaengine.h

Index: talk/media/webrtc/webrtcmediaengine.h
diff --git a/talk/media/webrtc/webrtcmediaengine.h b/talk/media/webrtc/webrtcmediaengine.h
index a3af1e73fb7c708398358384c6f05484f9768124..8d7540404dfc018844c80fd001649a65b89d37be 100644
--- a/talk/media/webrtc/webrtcmediaengine.h
+++ b/talk/media/webrtc/webrtcmediaengine.h
@@ -48,6 +48,14 @@ class WebRtcMediaEngineFactory {
       WebRtcVideoDecoderFactory* decoder_factory);
 };
 
+extern const char* kBweExtensionPriorities[];
+extern const size_t kBweExtensionPrioritiesLength;
+
+std::vector<RtpHeaderExtension> FilterRedundantRtpExtensions(
+    const std::vector<RtpHeaderExtension>& extensions,
+    const char* extension_prios[],
+    size_t extension_prios_length);
+
 }  // namespace cricket
 
 #endif  // TALK_MEDIA_WEBRTCMEDIAENGINE_H_