ppb_file_io_open: fix error handling, do return PP_ERROR_FAILED on failure
ppb_file_io_open: fix error handling, do return PP_ERROR_FAILED on failure

Papapashu/freshplayerplugin,reuben/freshplayerplugin,Papapashu/freshplayerplugin,grevutiu-gabriel/freshplayerplugin,grevutiu-gabriel/freshplayerplugin,Papapashu/freshplayerplugin,reuben/freshplayerplugin,reuben/freshplayerplugin