Remove obsolete path of getSources.

public/platform/WebMediaStreamCenter.h

Index: public/platform/WebMediaStreamCenter.h
diff --git a/public/platform/WebMediaStreamCenter.h b/public/platform/WebMediaStreamCenter.h
index a2610d0aeb15efbc5ab24f4d67f68d59110df252..2de456f48b0e3b4752d68ded8381b918ed699623 100644
--- a/public/platform/WebMediaStreamCenter.h
+++ b/public/platform/WebMediaStreamCenter.h
@@ -38,7 +38,6 @@ namespace blink {
 class WebAudioSourceProvider;
 class WebMediaStream;
 class WebMediaStreamTrack;
-class WebMediaStreamTrackSourcesRequest;
 class WebSourceInfo;
 class WebString;
 
@@ -46,8 +45,6 @@ class WebMediaStreamCenter {
 public:
     virtual ~WebMediaStreamCenter() { }
 
-    virtual bool getMediaStreamTrackSources(const WebMediaStreamTrackSourcesRequest&) { return false; }
-
     // Stream functionality.
     virtual void didCreateMediaStream(WebMediaStream&) = 0;
     virtual bool didAddMediaStreamTrack(const WebMediaStream&, const WebMediaStreamTrack&) = 0;