Add top level app element

appengine/swarming/elements/imp/common/auth-signin.html

Index: appengine/swarming/elements/imp/common/auth-signin.html
diff --git a/appengine/swarming/elements/imp/common/auth-signin.html b/appengine/swarming/elements/imp/common/auth-signin.html
index 635f68bbd45c444d8e4fc6d66f2bff419856adb8..13cd840a95db66a69925a25c678f7b7c958d5f5a 100644
--- a/appengine/swarming/elements/imp/common/auth-signin.html
+++ b/appengine/swarming/elements/imp/common/auth-signin.html
@@ -37,8 +37,11 @@
       #avatar {
         border-radius: 5px;
       }
-      #signinContainer {
-        margin-top: 14px;
+      a {
+        color: white;
+      }
+      .center {
+        vertical-align: middle;
       }
     </style>
 
@@ -56,10 +59,10 @@
     </template>
 
     <template is="dom-if" if="[[signedIn]]">
-      <img id="avatar" src="[[profile.imageUrl]]" width="30" height="30">
-      <span>[[profile.email]]</span>
-      <span>|</span>
-      <a on-tap="signOut" href="#">Sign out</a>
+      <img class="center" id="avatar" src="[[profile.imageUrl]]" width="30" height="30">
+      <span class="center" >[[profile.email]]</span>
+      <span class="center" >|</span>
+      <a class="center" on-tap="signOut" href="#">Sign out</a>
     </template>
   </template>
   <script>