Merge pull request #10533 from topsitemakers/master

adding required attribute for example signin form

examples/signin/index.html

@@ -29,8 +29,8 @@
 
       <form class="form-signin">
         <h2 class="form-signin-heading">Please sign in</h2>
-        <input type="text" class="form-control" placeholder="Email address" autofocus>
-        <input type="password" class="form-control" placeholder="Password">
+        <input type="text" class="form-control" placeholder="Email address" required autofocus>
+        <input type="password" class="form-control" placeholder="Password" required>
         <label class="checkbox">
           <input type="checkbox" value="remember-me"> Remember me
         </label>