use util hasOwn

Author: maciej-ka

src/core/instance/inject.js

@@ -3,6 +3,7 @@
 import { hasSymbol } from 'core/util/env'
 import { warn } from '../util/index'
 import { defineReactive } from '../observer/index'
+import { hasOwn } from '../../shared/util'
 
 export function initProvide (vm: Component) {
   const provide = vm.$options.provide
@@ -57,7 +58,7 @@ export function resolveInject (inject: any, vm: Component): ?Object {
         }
         source = source.$parent
       }
-      process.env.NODE_ENV !== 'production' && Object.keys(result).indexOf(key) < 0 &&
+      process.env.NODE_ENV !== 'production' && !hasOwn(result, key) &&
         warn(`Injection "${key}" not found`, vm)
     }
     return result