Merge branch 'dev' of github.com:yyx990803/vue into dev

Author: yyx990803

src/util/lang.js

@@ -172,7 +172,7 @@ exports.extend = function (to, from) {
  */
 
 exports.isObject = function (obj) {
-  return obj && typeof obj === 'object'
+  return obj !== null && typeof obj === 'object'
 }
 
 /**
@@ -195,9 +195,7 @@ exports.isPlainObject = function (obj) {
  * @return {Boolean}
  */
 
-exports.isArray = function (obj) {
-  return Array.isArray(obj)
-}
+exports.isArray = Array.isArray
 
 /**
  * Define a non-enumerable property

src/watcher.js

@@ -179,7 +179,7 @@ p.run = function () {
     var value = this.get()
     if (
       value !== this.value ||
-      Array.isArray(value) ||
+      _.isArray(value) ||
       this.deep
     ) {
       var oldValue = this.value