Auto merge of #6834 - jdm:named-constructor-prototype, r=Ms2ger

Use an actual byte string when defining the prototype of named constr…

…uctors. Fixes #6730.

r? @Ms2ger

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components/script/dom/bindings/utils.rs

@@ -233,7 +233,7 @@ pub fn do_create_interface_objects(cx: *mut JSContext,
         let constructor = RootedObject::new(cx, create_constructor(cx, cnative, cnargs, cs.as_ptr()));
         assert!(!constructor.ptr.is_null());
         unsafe {
-            assert!(JS_DefineProperty1(cx, constructor.handle(), "prototype".as_ptr() as *const libc::c_char,
+            assert!(JS_DefineProperty1(cx, constructor.handle(), b"prototype\0".as_ptr() as *const libc::c_char,
                                        rval.handle(),
                                        JSPROP_PERMANENT | JSPROP_READONLY,
                                        None, None) != 0);

tests/wpt/metadata/html/semantics/embedded-content/the-img-element/Image-constructor.html.ini

@@ -1,6 +0,0 @@
-[Image-constructor.html]
-  type: testharness
-  [Image and HTMLImageElement share a prototype]
-    expected:
-      if not debug: FAIL
-