Throw a TypeError when unwrapping an interface argument fails.

src/components/script/dom/bindings/codegen/CodegenRust.py

@@ -586,7 +586,15 @@ def getJSToNativeConversionTemplate(type, descriptorProvider, failureCode=None,
                             "argument" % descriptor.interface.identifier.name)
 
         if failureCode is None:
-            unwrapFailureCode = "return 0; //XXXjdm return Throw(cx, rv);"
+            substitutions = {
+                "sourceDescription": sourceDescription,
+                "interface": descriptor.interface.identifier.name,
+                "exceptionCode": exceptionCode,
+            }
+            unwrapFailureCode = string.Template(
+                'throw_type_error(cx, "${sourceDescription} does not '
+                'implement interface ${interface}.");\n'
+                '${exceptionCode}').substitute(substitutions)
         else:
             unwrapFailureCode = failureCode
 

src/test/wpt/metadata/dom/nodes/Node-insertBefore.html.ini

@@ -1,6 +1,11 @@
 [Node-insertBefore.html]
   type: testharness
-  expected: TIMEOUT
+  [If the context node is a document, inserting a document or text node should throw a HierarchyRequestError.]
-  [Calling insertBefore with a non-Node first argument must throw TypeError.]
+    expected: FAIL
-    expected: TIMEOUT
+
+  [If the context node is a DocumentFragment, inserting a document or a doctype should throw a HierarchyRequestError.]
+    expected: FAIL
+
+  [If the context node is an element, inserting a document or a doctype should throw a HierarchyRequestError.]
+    expected: FAIL