It will be used on Unix systems if the required dev package is
present. (Detected by a configure compile test.)
You can configure with -no-libproxy to avoid the dependency.
It will not be used on OS X or Windows, as we already implement
the native API for getting proxies there.
Currently we use whatever PAC runner is provided by the distro
for running PAC scripts - if we want to run PAC scripts using
Qt, then we would have to implement a pacrunner plugin to libproxy.
Note that their webkit pacrunner is using javascriptcore already.
Tested using the libproxy 0.4.7 that is included in Ubuntu 12.04.
Re-tested using Ubuntu 14.04 which ships libproxy 0.4.11.
It works except when both socks and http proxies are configured in
the manual settings - in that case libproxy returns only the socks
proxy. This seems to be covered by libproxy issue 119.
[ChangeLog][QtNetwork] Introduce libproxy backend for Unix platforms,
enabled automatically if the required dev package is present
Task-number: QTBUG-26295
Change-Id: I521c0a198fcf482386ea8a189114a0077778265c
Reviewed-by: Richard J. Moore <rich@kde.org>
