ResolverActivity: fix null pointer exception

if alwaysUseOption is true but mAdapter.hasFilteredItem() is not, we try
to set a LongClickListener on a non existant view.

move the assingment of the LongClickListener down to ensure
mAdapter.hasFilteredItem() is true.

Change-Id: I04df845325a9a21f5563292e56728dcc51e91623