Crashfix; don't crash in LLRightClickInventoryFetchDescendentsObserver::execute when there's a 0 pointer for item_array or cat_array.
Crashfix; don't crash in LLRightClickInventoryFetchDescendentsObserver::execute when there's a 0 pointer for item_array or cat_array.

gabeharms/firestorm,gabeharms/firestorm,gabeharms/firestorm,gabeharms/firestorm,gabeharms/firestorm,gabeharms/firestorm,gabeharms/firestorm,gabeharms/firestorm,gabeharms/firestorm