修复了编译报错的问题。review by 孙凯。

@@ -70,16 +70,18 @@ export default class BrandStore extends Component {
             duration: 255,
             children: message,
             animationEnd : () => {
-                this._toast && this._toast._toastAnimationToggle = setTimeout(
-                    () => {
-                        this._toast && this._toast.hide({
-                            duration: 0,
-                            animationEnd: () => {
-                                }
-                        })
-                     },
-                    1000
-                );
+                if(this._toast){
+                    this._toast._toastAnimationToggle = setTimeout(
+                        () => {
+                            this._toast && this._toast.hide({
+                                duration: 0,
+                                animationEnd: () => {
+                                    }
+                            })
+                         },
+                        1000
+                    );
+                }
             }
         })
     }