Bug 904085 - Fixed bug from previous related commit r=gregor

https://bugzilla.mozilla.org/show_bug.cgi?id=904085

The previous commit in master (4cc6143c) did not take into consideration a small code difference between master and v1-train in the updateShortcutIcons() function. This is the fix.

Now that the code is fixed, take a look at the "games" icon -  it's made of 3 icons. Click "games", wait for results to show up, click back - now the "games" icon has been updated those the first 3 results.