[Tizen ]Fire storage event at window when storageArea change

According to the spec http://dev.w3.org/html5/webstorage/#dom-storage-clear,
'When the setItem(), removeItem(), and clear() methods are invoked, events
are fired on the Window objects'. This change will implement this feature.

BUG=XWALK-2991
Here, I want to exclude the frame which fire the storage event. I think the focused frame is the event source. So I add this check.