Get rid of last uses of deprecated toWebCoreString(v8::Handle<v8::Value>)

Source/bindings/v8/custom/V8BiquadFilterNodeCustom.cpp

Index: Source/bindings/v8/custom/V8BiquadFilterNodeCustom.cpp
diff --git a/Source/bindings/v8/custom/V8BiquadFilterNodeCustom.cpp b/Source/bindings/v8/custom/V8BiquadFilterNodeCustom.cpp
index 09e5e8579e9bbb3560d2058b3cb9b680dc6d5cd0..ea209654ec7e37016074dfcbfdd10b34d0e395b1 100644
--- a/Source/bindings/v8/custom/V8BiquadFilterNodeCustom.cpp
+++ b/Source/bindings/v8/custom/V8BiquadFilterNodeCustom.cpp
@@ -45,7 +45,7 @@ void V8BiquadFilterNode::typeAttributeSetterCustom(v8::Local<v8::Value> value, c
     }
 
     if (value->IsString()) {
-        String type = toWebCoreString(value);
+        String type = toWebCoreString(value.As<v8::String>());
         if (type == "lowpass" || type == "highpass" || type == "bandpass" || type == "lowshelf" || type == "highshelf" || type == "peaking" || type == "notch" || type == "allpass") {
             imp->setType(type);
             return;