Bookmarks tree has slightly oversized margins. r=hewitt sr=hyatt

themes/modern/communicator/bookmarks/bookmarksWindow.css

@@ -33,3 +33,7 @@
  display: none !important; 
 } 
 
+.bookmarks-window-tree {
+  border: none;
+  margin: 0px !important;
+}

themes/modern/communicator/communicator.css

@@ -62,3 +62,8 @@
 .down[disabled="true"] {
   list-style-image: url("chrome://global/skin/arrow/arrow-dn-dis.gif");
 }
+
+.sidebarTree {
+  border: none;
+  margin: 0px !important;
+}