Remove USE(GSTREAMER) and USE(WEBAUDIO_GSTREAMER) guards.

Source/core/platform/audio/FFTFrame.h

Index: Source/core/platform/audio/FFTFrame.h
diff --git a/Source/core/platform/audio/FFTFrame.h b/Source/core/platform/audio/FFTFrame.h
index 522cb5fbc802a3f91a210d13498d83a25964b35d..cff4917a67055b0a46203aef443f812def12f76a 100644
--- a/Source/core/platform/audio/FFTFrame.h
+++ b/Source/core/platform/audio/FFTFrame.h
@@ -47,13 +47,6 @@
 #include "mkl_dfti.h"
 #endif // USE(WEBAUDIO_MKL)
 
-#if USE(WEBAUDIO_GSTREAMER)
-#include <glib.h>
-G_BEGIN_DECLS
-#include <gst/fft/gstfftf32.h>
-G_END_DECLS
-#endif // USE(WEBAUDIO_GSTREAMER)
-
 #if USE(WEBAUDIO_OPENMAX_DL_FFT)
 #include "dl/sp/api/armSP.h"
 #include "dl/sp/api/omxSP.h"
@@ -162,14 +155,6 @@ private:
     AudioFloatArray m_imagData;
 #endif // USE(WEBAUDIO_FFMPEG)
 
-#if USE(WEBAUDIO_GSTREAMER)
-    GstFFTF32* m_fft;
-    GstFFTF32* m_inverseFft;
-    GstFFTF32Complex* m_complexData;
-    AudioFloatArray m_realData;
-    AudioFloatArray m_imagData;
-#endif // USE(WEBAUDIO_GSTREAMER)
-
 #if USE(WEBAUDIO_IPP)
     Ipp8u* m_buffer;
     IppsDFTSpec_R_32f* m_DFTSpec;