Make the icon caching for SD cards actually work.

We need to save the icon *after* we have loaded all the other information about it.

Also, add a check that if apps on SD aren't possible, don't even bother saving the icon.  This saves
~200 ms on each run of the loader.

Bug: 3240615
Change-Id: Idc2329a868ab970b51deec341ffa8a47a344e110
1 file changed