Test runner: Detect extra property in 'actual' but not in 'expected'. (#407)

* Test runner: Detect extra property in 'actual' but not in 'expected'.

Also update all expected.json where this would result in errors.

* Include rmExpected.js script in case it is needed again

test/fixtures/esprima/declaration-function/migrated_0010/expected.json

@@ -69,7 +69,8 @@
                 "end": {
                   "line": 1,
                   "column": 6
-                }
+                },
+                "identifierName": "hi"
               },
               "name": "hi"
             },
@@ -99,12 +100,14 @@
                   "end": {
                     "line": 1,
                     "column": 27
-                  }
+                  },
+                  "identifierName": "arguments"
                 },
                 "name": "arguments"
               },
               "generator": false,
               "expression": false,
+              "async": false,
               "params": [],
               "body": {
                 "type": "BlockStatement",
@@ -120,13 +123,15 @@
                     "column": 33
                   }
                 },
-                "body": []
+                "body": [],
+                "directives": []
               }
             }
           }
         ],
         "kind": "var"
       }
-    ]
+    ],
+    "directives": []
   }
 }