Remove type of panningModelType "soundfield".

Source/bindings/v8/custom/V8PannerNodeCustom.cpp

 /*
  * Copyright (C) 2012, Google Inc. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions
  * are met:
  * 1.  Redistributions of source code must retain the above copyright
  *    notice, this list of conditions and the following disclaimer.
  * 2.  Redistributions in binary form must reproduce the above copyright
  *    notice, this list of conditions and the following disclaimer in the
@@ skipping 32 matching lines @@
             return;
         if (!imp->setPanningModel(model)) {
             exceptionState.throwTypeError("Illegal panningModel");
             exceptionState.throwIfNeeded();
         }
         return;
     }
 
     if (value->IsString()) {
         String model = toCoreString(value.As<v8::String>());
-        if (model == "equalpower" || model == "HRTF" || model == "soundfield") {
+        if (model == "equalpower" || model == "HRTF") {
             imp->setPanningModel(model);
             return;
         }
     }
 
     exceptionState.throwTypeError("Illegal panningModel");
     exceptionState.throwIfNeeded();
 }
 
 void V8PannerNode::distanceModelAttributeSetterCustom(v8::Local<v8::Value> value, const v8::PropertyCallbackInfo<void>& info)
@@ skipping 20 matching lines @@
         }
     }
 
     exceptionState.throwTypeError("Illegal distanceModel");
     exceptionState.throwIfNeeded();
 }
 
 } // namespace WebCore
 
 #endif // ENABLE(WEB_AUDIO)