Like before, this is taken from the existing QUrl code and is optimized for
ASCII handling (for the same reasons). And like previously, make
QString::fromUtf8 use a stateless version of the codec, which is faster.
There's a small change in behavior in the decoding: we insert a U+FFFD for
each byte that cannot be decoded properly. Previously, it would "eat" all bad
high-bit bytes and replace them all with one single U+FFFD. Either behavior is
allowed by the UTF-8 specifications, even though this new behavior will cause
misalignment in the Bradley Kuhn sample UTF-8 text.
Change-Id: Ib1b1f0b4291293bab345acaf376e00204ed87565
Reviewed-by: Olivier Goffart <ogoffart@woboq.com>
Reviewed-by: Thiago Macieira <thiago.macieira@intel.com>
8dd47e34b9