QAnyStringView: add substringing operations

Add the full set of substringing operations:
- mid/left/right (old-style)
- sliced/first/last (new style)
- chop/chopped/truncate

The implementation is copied from QUtf8StringView, adjusted to use
sliced() instead of the (ptr, n) ctor, so we need to deal with the tag
twiddling only once, in sliced().

The documentation is also copied from QUtf8StringView.

[ChangeLog][QtCore][QAnyStringView] Added substring functions
sliced(), first(), last(), chop()/chopped(), truncate().

Change-Id: Ief454e9694519e97d9146fa84bc05dda1dded046
Reviewed-by: Mårten Nordheim <marten.nordheim@qt.io>
Reviewed-by: Mate Barany <mate.barany@qt.io>
Reviewed-by: Ivan Solovev <ivan.solovev@qt.io>
Reviewed-by: Thiago Macieira <thiago.macieira@intel.com>

0 files changed, 0 insertions, 0 deletions