Bug 835111 - always open new chat windows in the 'most recent' suitable browser window. r=gavin

browser/base/content/test/social/browser_social_chatwindow.js

@@ -456,18 +456,17 @@ var tests = {
     ok(!window.SocialChatBar.hasChats, "first window should start with no chats");
     openChat(function() {
       ok(window.SocialChatBar.hasChats, "first window has the chat");
-      // create a second window - although this will be the "most recent",
-      // the fact the first window has a chat open means the first will be targetted.
+      // create a second window - this will be the "most recent" and will
+      // therefore be the window that hosts the new chat (see bug 835111)
       let secondWindow = OpenBrowserWindow();
       secondWindow.addEventListener("load", function loadListener() {
         secondWindow.removeEventListener("load", loadListener);
         ok(!secondWindow.SocialChatBar.hasChats, "second window has no chats");
         openChat(function() {
-          ok(!secondWindow.SocialChatBar.hasChats, "second window still has no chats");
-          is(window.SocialChatBar.chatbar.childElementCount, 2, "first window now has 2 chats");
+          ok(secondWindow.SocialChatBar.hasChats, "second window now has chats");
+          is(window.SocialChatBar.chatbar.childElementCount, 1, "first window still has 1 chat");
           window.SocialChatBar.chatbar.removeAll();
-          // now open another chat - it should open in the second window (as
-          // it is the "most recent" and no other windows have chats)
+          // now open another chat - it should still open in the second.
           openChat(function() {
             ok(!window.SocialChatBar.hasChats, "first window has no chats");
             ok(secondWindow.SocialChatBar.hasChats, "second window has a chat");

toolkit/components/social/MozSocialAPI.jsm

@@ -235,10 +235,10 @@ function isWindowGoodForChats(win) {
 function findChromeWindowForChats(preferredWindow) {
   if (preferredWindow && isWindowGoodForChats(preferredWindow))
     return preferredWindow;
-  // no good - so let's go hunting.  We are now looking for a navigator:browser
-  // window that is suitable and already has chats open, or failing that,
-  // any suitable navigator:browser window.
-  let first, best, enumerator;
+  // no good - we just use the "most recent" browser window which can host
+  // chats (we used to try and "group" all chats in the same browser window,
+  // but that didn't work out so well - see bug 835111
+  let topMost, enumerator;
   // *sigh* - getZOrderDOMWindowEnumerator is broken everywhere other than
   // Windows.  We use BROKEN_WM_Z_ORDER as that is what the c++ code uses
   // and a few bugs recommend searching mxr for this symbol to identify the
@@ -254,13 +254,10 @@ function findChromeWindowForChats(preferredWindow) {
   }
   while (enumerator.hasMoreElements()) {
     let win = enumerator.getNext();
-    if (win && isWindowGoodForChats(win)) {
-      first = win;
-      if (win.SocialChatBar.hasChats)
-        best = win;
-    }
+    if (win && isWindowGoodForChats(win))
+      topMost = win;
   }
-  return best || first;
+  return topMost;
 }
 
 this.openChatWindow =