MDL-34300 JavaScript: Stop YUI from forcing z-index on moodle-core-notification

lib/yui/notification/notification.js

@@ -77,6 +77,10 @@ Y.extend(DIALOGUE, Y.Panel, {
         this.after('visibleChange', this.visibilityChanged, this);
         this.render();
         this.show();
+
+        // Workaround upstream YUI bug http://yuilibrary.com/projects/yui3/ticket/2532507
+        // and allow setting of z-index in theme.
+        this.get('boundingBox').setStyle('zIndex', null);
     },
     visibilityChanged : function(e) {
         var titlebar;

theme/base/style/core.css

@@ -864,7 +864,7 @@ sup {vertical-align: super;}
     background: none;
     border: none;
     /* Override the z-index set incorrectly by the YUI dialogue */
-    z-index: 600!important;
+    z-index: 600;
 }