Bug 516724: Taps in the awesomescreen above/below items don't register as hits, r=mfinkle

mobile/chrome/content/bindings.xml

@@ -356,16 +356,20 @@
     <handlers>
       <handler event="click" button="0">
         <![CDATA[
-          let originalTarget = event.originalTarget;
-          let target = originalTarget.parentNode;
-          if (originalTarget == this._allBookmarksItem || target == this._allBookmarksItem) {
+          let target = event.originalTarget;
+          if (target.localName != "autocompleteresult")
+            target = target.parentNode;
+          if (target.localName != "autocompleteresult")
+            return;
+
+          if (target == this._allBookmarksItem) {
             // XXX bug 516575
             // select the item, since closing the popup can be slow...
             // we should stop doing this when that isn't the case
             this.selectedIndex = 0;
             this.close();
             CommandUpdater.doCommand("cmd_bookmarks");
-          } else if (target.localName == "autocompleteresult" && target._empty != true) {
+          } else if (!target._empty) {
             let offset = this._allBookmarksItem._hidden ? 0 : 1;
             // XXX bug 516575
             // same as above - we can just set _selectedIndex directly to avoid