Fix QFileDialog not remembering the last visited directory.
Summary: This regression (compared to kdelibs4's direct KFileDialog usage) came from the fact that QFileDialog's lastVisited() only gets updated if the helper emits directoryEntered. So QFileDialog was setting the current dir as startDir every single time, overriding's KFileWidget's own logic for reusing the last dir initially. Test Plan: QFileDialog::getOpenFileName(this, i18n("Select file")); twice in a row, from the same process. Reviewers: anthonyfieroni, elvisangelaccio, plasma-devel, broulik, arichardson, ngraham Reviewed By: ngraham Subscribers: ngraham, apol Tags: #plasma Differential Revision: https://phabricator.kde.org/D14437 (cherry picked from commit b269980d)