remove v-repeat focus (perf reasons)

src/directives/repeat.js

@@ -237,7 +237,6 @@ module.exports = {
    */
 
   diff: function (data, oldVms) {
-    var activeElement = document.activeElement
     var idKey = this.idKey
     var converted = this.converted
     var anchor = this.anchor
@@ -328,9 +327,6 @@ module.exports = {
       }
       vm._reused = false
     }
-    if (activeElement) {
-      activeElement.focus()
-    }
     return vms
   },