docs: add some demos for weapp

src/loading/demo/index.vue

@@ -13,19 +13,13 @@
       />
     </demo-block>
 
-    <demo-block
-      v-if="!$attrs.weapp"
-      :title="$t('text')"
-    >
+    <demo-block :title="$t('text')">
       <van-loading size="24px">
         {{ $t('loading') }}
       </van-loading>
     </demo-block>
 
-    <demo-block
-      v-if="!$attrs.weapp"
-      :title="$t('vertical')"
-    >
+    <demo-block :title="$t('vertical')">
       <van-loading
         size="24px"
         vertical

src/popup/demo/index.vue

@@ -17,7 +17,7 @@
       <van-popup v-model="showRight" position="right" :style="{ width: '20%', height: '100%' }" />
     </demo-block>
 
-    <demo-block v-if="!$attrs.weapp" :title="$t('closeIcon')">
+    <demo-block :title="$t('closeIcon')">
       <van-cell :title="$t('closeIcon')" is-link @click="showCloseIcon = true" />
       <van-cell :title="$t('customCloseIcon')" is-link @click="showCustomCloseIcon = true" />
       <van-cell :title="$t('customIconPosition')" is-link @click="showCustomIconPosition = true" />
@@ -39,7 +39,7 @@
       />
     </demo-block>
 
-    <demo-block v-if="!$attrs.weapp" :title="$t('roundCorner')">
+    <demo-block :title="$t('roundCorner')">
       <van-cell :title="$t('roundCorner')" is-link @click="showRoundCorner = true" />
       <van-popup v-model="showRoundCorner" round position="bottom" :style="{ height: '20%' }" />
     </demo-block>

src/slider/demo/index.vue

@@ -51,10 +51,7 @@
       </van-slider>
     </demo-block>
 
-    <demo-block
-      v-if="!$attrs.weapp"
-      :title="$t('vertical')"
-    >
+    <demo-block v-if="!$attrs.weapp" :title="$t('vertical')">
       <div :style="{ height: '120px', paddingLeft: '30px' }">
         <van-slider
           v-model="value7"

src/tab/demo/index.vue

@@ -99,7 +99,7 @@
       </van-tabs>
     </demo-block>
 
-    <demo-block :title="$t('title7')">
+    <demo-block v-if="!$attrs.weapp" :title="$t('title7')">
       <van-tabs :active="active">
         <van-tab
           v-for="index in 2"