add css change to cohort dropdown for zoom support

.redcar/lucene_last_updated

@@ -1 +1 @@
-1360356040
+1360356243

.redcar/tags

@@ -1,4 +1,4 @@
-1360356040
+1360356243
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 B	/home/kevin/mitx_all/mitx/common/static/js/capa/jsme/jsme_export.nocache.js	function B()
 B	/home/kevin/mitx_all/mitx/common/static/js/capa/protex/protex.nocache.js	function B(){var b=false;try{var c=m.location.search;return (c.indexOf(U)!=-1||(c.indexOf(V)!=-1||m.external&&m.external.gwtOnLoad))&&c.indexOf(W)==-1}catch(a){}B=function()

lms/static/sass/_discussion.scss

@@ -977,7 +977,7 @@ body.discussion {
   }
 
   .sort-bar {
-    height: 27px;
+    height: auto;
     border-bottom: 1px solid #a3a3a3;
     @include linear-gradient(top, rgba(255, 255, 255, .3), rgba(255, 255, 255, 0));
     background-color: #aeaeae;