url parse and file invalid error report

tower: https://tower.im/projects/d4e0ff64158645f28d99a9ca72d0c27b/todos/f0014f7fdb65472da27597658b9f9c00/

removed playlist drag support, made a more specific drag solution,
and provide error report on draging lots of files in

Change-Id: Ib4bd9b7c5bf414a4cfcc183ab97922468b07a864