Bug 891736 - Make XUL menulist fire events. r=mfinkle

mobile/android/chrome/content/SelectHelper.js

@@ -41,10 +41,13 @@ var SelectHelper = {
       if (selected == -1)
           return;
 
-      let changed = false;
       if (aElement instanceof Ci.nsIDOMXULMenuListElement) {
+        if (aElement.selectedIndex != selected) {
           aElement.selectedIndex = selected;
+          this.fireOnCommand(aElement);
+        }
       } else if (aElement instanceof HTMLSelectElement) {
+        let changed = false;
         if (!Array.isArray(selected)) {
           let temp = [];
           for (let i = 0; i <= list.length; i++) {
@@ -61,10 +64,10 @@ var SelectHelper = {
           }
           i++
         });
-      }
 
         if (changed)
           this.fireOnChange(aElement);
+      }
     }).bind(this));
   },
 
@@ -128,5 +131,15 @@ var SelectHelper = {
     setTimeout(function() {
       aElement.dispatchEvent(evt);
     }, 0);
+  },
+
+  fireOnCommand: function(aElement) {
+    let evt = aElement.ownerDocument.createEvent("XULCommandEvent");
+    evt.initCommandEvent("command", true, true, aElement.defaultView, 0,
+                  false, false,
+                  false, false, null);
+    setTimeout(function() {
+      aElement.dispatchEvent(evt);
+    }, 0);
   }
 };