fix[TagsView]: fixed click.middle can close affixed tag bug (#2649)

src/layout/components/TagsView/index.vue

@@ -9,27 +9,18 @@
         :to="{ path: tag.path, query: tag.query, fullPath: tag.fullPath }"
         tag="span"
         class="tags-view-item"
-        @click.middle.native="closeSelectedTag(tag)"
+        @click.middle.native="!isAffix(tag)?closeSelectedTag(tag):''"
         @contextmenu.prevent.native="openMenu(tag,$event)"
       >
         {{ generateTitle(tag.title) }}
-        <span v-if="!tag.meta.affix" class="el-icon-close" @click.prevent.stop="closeSelectedTag(tag)" />
+        <span v-if="!isAffix(tag)" class="el-icon-close" @click.prevent.stop="closeSelectedTag(tag)" />
       </router-link>
     </scroll-pane>
     <ul v-show="visible" :style="{left:left+'px',top:top+'px'}" class="contextmenu">
-      <li @click="refreshSelectedTag(selectedTag)">
-        {{ $t('tagsView.refresh') }}
-      </li>
-      <li v-if="!(selectedTag.meta&&selectedTag.meta.affix)" @click="closeSelectedTag(selectedTag)">
-        {{
-          $t('tagsView.close') }}
-      </li>
-      <li @click="closeOthersTags">
-        {{ $t('tagsView.closeOthers') }}
-      </li>
-      <li @click="closeAllTags(selectedTag)">
-        {{ $t('tagsView.closeAll') }}
-      </li>
+      <li @click="refreshSelectedTag(selectedTag)">{{ $t('tagsView.refresh') }}</li>
+      <li v-if="!isAffix(selectedTag)" @click="closeSelectedTag(selectedTag)">{{ $t('tagsView.close') }}</li>
+      <li @click="closeOthersTags">{{ $t('tagsView.closeOthers') }}</li>
+      <li @click="closeAllTags(selectedTag)">{{ $t('tagsView.closeAll') }}</li>
     </ul>
   </div>
 </template>
@@ -80,6 +71,9 @@ export default {
     isActive(route) {
       return route.path === this.$route.path
     },
+    isAffix(tag) {
+      return tag.meta && tag.meta.affix
+    },
     filterAffixTags(routes, basePath = '/') {
       let tags = []
       routes.forEach(route => {