Repair copying file to VFAT without warnings.
Summary:
The refactoring returned the wrong value, which led to warnings,
but it was also in the wrong place. We want KIO::chown() to fail
explicitly, while we want chown during a file copy to be ignored
on e.g. VFAT systems.
Test Plan: Copying a file to a VFAT partition no longer warns/errors.
Reviewers: chinmoyr, markg, jtamate
Reviewed By: jtamate
Subscribers: Frameworks
Tags: Frameworks
Differential Revision: https://phabricator.kde.org/D10358
(cherry picked from commit 186fef79bf0415b4512b7ca3bb236dd7e30d8d20)