[ElMenu]: active menuitem which matches user specfied route

packages/menu/src/menu.vue

@@ -107,6 +107,14 @@
       },
       openActiveItemMenus() {
         let index = this.activeIndex;
+        // 选中用户指定的路由对应的menu
+        if (this.router) {
+          const userSpecifiedIndexs = Object
+                                       .keys(this.menuItems)
+                                       .filter(k => this.menuItems[k].route)
+                                       .filter(k => this.menuItems[k].route.path === this.$route.path);
+          userSpecifiedIndexs.length && (index = this.activeIndex = userSpecifiedIndexs[0]);
+        }
         if (!this.menuItems[index]) return;
         if (index && this.mode === 'vertical') {
           let indexPath = this.menuItems[index].indexPath;