change to basic file info on WinRT

FILE_FULL_DIR_INFO failed under certain circumstances on WinRT and
provides far more information than required. Hence prefer the basic
version in every case and standard for files with size description.

Change-Id: I63f1365f83cdd5d69f81278411f822dbd361fa92
Reviewed-by: Oliver Wolff <oliver.wolff@digia.com>