ChromeOS OOBE: fix focus flow in MD-OOBE.

chrome/browser/resources/chromeos/login/oobe_dialog.js

Index: chrome/browser/resources/chromeos/login/oobe_dialog.js
diff --git a/chrome/browser/resources/chromeos/login/oobe_dialog.js b/chrome/browser/resources/chromeos/login/oobe_dialog.js
index 9496e39dc8a9002dd7b349a1ebe2c4f0377ec9a2..ab3be0620f8b3505afc2cb202b6953ee4c75f553 100644
--- a/chrome/browser/resources/chromeos/login/oobe_dialog.js
+++ b/chrome/browser/resources/chromeos/login/oobe_dialog.js
@@ -23,4 +23,17 @@ Polymer({
       reflectToAttribute: true,
     },
   },
+
+  focus: function() {},
+
+  /**
+    * This is called from oobe_welcome when this dialog is shown.
+    */
+  show: function() {
+    var focusedElements = this.getElementsByClassName('focus-on-show');
+    if (focusedElements)
+      focusedElements[0].focus();
+
+    this.fire('show-dialog');
+  },
 });