LibJS: Add "name" property to functions

Author: https://github.com/linusg
Commit: 99be27b4a1
Pull-request: https://github.com/SerenityOS/serenity/pull/2068

Libraries/LibJS/Tests/Boolean.js

@@ -2,6 +2,9 @@ load("test-common.js");
 
 try {
     assert(Boolean.length === 1);
+    assert(Boolean.name === "Boolean");
+    assert(Boolean.prototype.length === undefined);
+
     assert(typeof new Boolean() === "object");
     assert(new Boolean().valueOf() === false);