CoreText: Avoid populating font family aliases if family was populated

When trying to match a font request to fonts in the database we might
end up with a mismatch due to the style not being available, but the
font family itself was.

If that's the case there's no point in trying to populate font aliases.

Fixes: QTBUG-98369
Fixes: QTBUG-99216
Pick-to: 6.3 6.2 5.15
Change-Id: I8776e5b89588a13749c9c7e414c5bfac86feab58
Reviewed-by: Eskil Abrahamsen Blomfeldt <eskil.abrahamsen-blomfeldt@qt.io>

src/gui/text/coretext/qcoretextfontdatabase.mm

@@ -151,6 +151,12 @@ void QCoreTextFontDatabase::populateFontDatabase()
 bool QCoreTextFontDatabase::populateFamilyAliases(const QString &missingFamily)
 {
 #if defined(Q_OS_MACOS)
+    if (isFamilyPopulated(missingFamily)) {
+        // We got here because one of the other properties of the font mismatched,
+        // for example the style, so there's no point in populating font aliases.
+        return false;
+    }
+
     if (m_hasPopulatedAliases)
         return false;