Otherwise, values that are composed of others are not handled
correctly. For example,
Qt::Dialog|Qt::FramelessWindowHint (Qt::Dialog=0x2|Qt::Window)
is currently output as
"Window|FramelessWindowHint" since
Qt::Window matches first and its bits are removed from the flag value
so that Qt::Dialog in the next iteration no longer matches.
Change-Id: I67db5c977c75f887392aa8f345c5e6e9d82c5c26
Reviewed-by: Olivier Goffart (Woboq GmbH) <ogoffart@woboq.com>