Bug 868217 - Hide sync flyout description when sync is setup properly. r=ally

browser/metro/base/content/browser.xul

@@ -379,10 +379,10 @@
     </flyoutpanel>
 
     <flyoutpanel id="sync-flyoutpanel" headertext="&syncHeader.title;">
-      <description>&sync.setup.description;</description> 
-      <description id="sync-accountinfo" collapsed="true"></description> 
-      <description id="sync-lastsync" collapsed="true"></description> 
-      <description id="sync-errordescription" collapsed="true"></description> 
+      <description id="sync-description">&sync.setup.description;</description>
+      <description id="sync-accountinfo" collapsed="true"></description>
+      <description id="sync-lastsync" collapsed="true"></description>
+      <description id="sync-errordescription" collapsed="true"></description>
       <setting id="sync-connect" type="control" collapsed="true">
         <button label="&sync.setupbutton.label;" oncommand="Sync.tryConnect();" />
       </setting>

browser/metro/base/content/sync.js

@@ -447,7 +447,7 @@ let Sync = {
 
     let settingids = ["device", "connect", "connected", "disconnect", "lastsync", "pairdevice",
                       "errordescription", "accountinfo", "disconnectwarnpanel", "disconnectthrobber",
-                      "disconnectwarntitle"];
+                      "disconnectwarntitle", "description"];
     settingids.forEach(function(id) {
       elements[id] = document.getElementById("sync-" + id);
     });
@@ -468,6 +468,7 @@ let Sync = {
     let lastsync = this._elements.lastsync;
     let pairdevice = this._elements.pairdevice;
     let accountinfo = this._elements.accountinfo;
+    let description = this._elements.description;
     let disconnectthrobber = this._elements.disconnectthrobber;
 
     // This gets updated when an error occurs
@@ -489,6 +490,7 @@ let Sync = {
     lastsync.collapsed = !isConfigured;
     device.collapsed = !isConfigured;
     disconnect.collapsed = !isConfigured;
+    description.collapsed = isConfigured;
 
     if (this._disconnecting) {
       connect.collapsed = true;