QLatin1String::mid() etc were changed from narrow to wide contract,
but the narrow-contract replacements weren't added. This blocks using
the narrow-contract functions in QStringTokenizer.
As a drive-by, Q_REQUIRED_RESULT -> [[nodiscard]] and Q_DECL_CONSTEXPR
-> constexpr. Also centralize most Q_ASSERT()s in a single function,
verify(), in an attempt to reduce the amount of string data generated
from the asserts in assertive builds.
[ChangeLog][QtCore][QLatin1String] Added from(), sliced(), first(n),
last(n) functions.
[ChangeLog][QtCore][QLatin1String] size_type/size() is now qsizetype
(was: int). This makes QLatin1String(ptr, 0) ambiguous now between the
(ptr, ptr) and (ptr, qsizetype) constructors.
Change-Id: Ie195f66ae1974eb0752c058aa9f3b0853ed92477
Reviewed-by: Lars Knoll <lars.knoll@qt.io>
Reviewed-by: Thiago Macieira <thiago.macieira@intel.com>