MD History: Show 'no synced tabs' when tab sync is disabled

chrome/browser/resources/md_history/synced_device_manager.js

Index: chrome/browser/resources/md_history/synced_device_manager.js
diff --git a/chrome/browser/resources/md_history/synced_device_manager.js b/chrome/browser/resources/md_history/synced_device_manager.js
index 433fb7f88a5487479147853bbbf669a99f3ef12d..964ba848934dd789240b45899069f38f8298a712 100644
--- a/chrome/browser/resources/md_history/synced_device_manager.js
+++ b/chrome/browser/resources/md_history/synced_device_manager.js
@@ -189,6 +189,14 @@ Polymer({
   },
 
   /**
+   * End fetching synced tabs when sync is disabled.
+   */
+  tabSyncDisabled: function() {
+    this.fetchingSyncedTabs_ = false;
+    this.clearDisplayedSyncedDevices_();
+  },
+
+  /**
    * Get called when user's sign in state changes, this will affect UI of synced
    * tabs page. Sign in promo gets displayed when user is signed out, and
    * different messages are shown when there are no synced tabs.