Fix incorrect test in HasDataProperty, bug 699166.

js/src/jit-test/tests/basic/bug699166.js

@@ -0,0 +1,7 @@
+a = "".__proto__
+b = uneval().__proto__
+for (var i = 0; i < 2; i++) {
+    a.__defineSetter__("valueOf", function() {})
+    a + ""
+    delete b.valueOf
+}

js/src/jsobj.cpp

@@ -6654,7 +6654,8 @@ bool
 HasDataProperty(JSContext *cx, JSObject *obj, jsid methodid, Value *vp)
 {
     if (const Shape *shape = obj->nativeLookup(cx, methodid)) {
-        if (shape->hasDefaultGetterOrIsMethod() && obj->containsSlot(shape->maybeSlot())) {
+        if (shape->hasDefaultGetterOrIsMethod() && shape->hasSlot()) {
+            JS_ASSERT(obj->containsSlot(shape->slot()));
             *vp = obj->nativeGetSlot(shape->slot());
             return true;
         }