添加带有 icon 的样式

components/tabs/demo/icon.md

@@ -0,0 +1,28 @@
+# 图标
+
+- order: 2
+
+带有图标。
+
+---
+
+````jsx
+var Tab = antd.Tab;
+var TabPane = Tab.TabPane;
+
+function callback() {}
+
+var tabContent = [
+  <span><i className="anticon anticon-lock"></i>tab 1</span>,
+  <span><i className="anticon anticon-lock"></i>tab 2</span>,
+  <span><i className="anticon anticon-lock"></i>tab 3</span>,
+]
+
+React.render(
+  <Tab defaultActiveKey="2" onChange={callback}>
+    <TabPane tab={tabContent[0]} key="1">选项卡一</TabPane>
+    <TabPane tab={tabContent[1]} key="2">选项卡一</TabPane>
+    <TabPane tab={tabContent[2]} key="3">选项卡一</TabPane>
+  </Tab>
+, document.getElementById('components-tabs-demo-icon'));
+````

style/components/tab.less

@@ -152,6 +152,14 @@
         font-weight: 500;
         display: block;
         color: #666;
+
+        .anticon {
+          width: 14px;
+          height: 14px;
+          margin-right: 12px;
+          top: -1px;
+        }
+
       }
 
       > a:hover {