Fix QString::localeAwareCompare with composed/decomposed strings on Windows

With ICU and on macOS it appears that the comparison is done on a
canonical form, while CompareString(Ex) does not do that, as the added
test verifies. Explicit normalization fixes that.

As a bonus, this also unifies the code path between regular Windows
and UWP by unconditionally using CompareStringEx (which requires
Vista or later).

This issue surfaced while running the ECMASCript 6 Conformance Test
Suite in QtQml.

This re-uses the existing test for localeAwareCompare, which was
disabled on Windows, macOS and Linux with ICU (the common case).

Change-Id: I52440fce60b54745ead1eff005ec51e98e2a79ec
Reviewed-by: Friedemann Kleint <Friedemann.Kleint@qt.io>
Reviewed-by: Thiago Macieira <thiago.macieira@intel.com>
Reviewed-by: Konstantin Ritt <ritt.ks@gmail.com>

0 files changed, 0 insertions, 0 deletions