IDL compiler: move EventHandler null check out of generated bindings

Source/bindings/scripts/code_generator_v8.pm

Index: Source/bindings/scripts/code_generator_v8.pm
diff --git a/Source/bindings/scripts/code_generator_v8.pm b/Source/bindings/scripts/code_generator_v8.pm
index a4b0c0049cf641624abfebcbd0302fc23fd5aa7c..37e4144f6364ebfb1d2702be790cf53630593049 100644
--- a/Source/bindings/scripts/code_generator_v8.pm
+++ b/Source/bindings/scripts/code_generator_v8.pm
@@ -1955,9 +1955,6 @@ END
 
     if ($attribute->type eq "EventHandler") {
         my $implSetterFunctionName = FirstLetterToUpperCase($attrName);
-        # Non callable input should be treated as null
-        $code .= "    if (!jsValue->IsNull() && !jsValue->IsFunction())\n";
-        $code .= "        jsValue = v8::Null(info.GetIsolate());\n";
         if (!InheritsInterface($interface, "Node")) {
             my $attrImplName = GetImplName($attribute);
             $code .= "    transferHiddenDependency(info.Holder(), imp->${attrImplName}(isolatedWorldForIsolate(info.GetIsolate())), jsValue, ${v8ClassName}::eventListenerCacheIndex, info.GetIsolate());\n";