matchIconSize

auto fixed = IconSubDir(32, IconSubDir.Type.Fixed);
assert(matchIconSize(fixed, fixed.size()));
assert(!matchIconSize(fixed, fixed.size() - 2));

auto threshold = IconSubDir(32, IconSubDir.Type.Threshold, "", 0, 0, 5);
assert(matchIconSize(threshold, threshold.size() + threshold.threshold()));
assert(matchIconSize(threshold, threshold.size() - threshold.threshold()));
assert(!matchIconSize(threshold, threshold.size() + threshold.threshold() + 1));
assert(!matchIconSize(threshold, threshold.size() - threshold.threshold() - 1));

auto scalable = IconSubDir(32, IconSubDir.Type.Scalable, "", 24, 48);
assert(matchIconSize(scalable, scalable.minSize()));
assert(matchIconSize(scalable, scalable.maxSize()));
assert(!matchIconSize(scalable, scalable.minSize() - 1));
assert(!matchIconSize(scalable, scalable.maxSize() + 1));