Utils: Wrap various file system iteration flags and filters

... into a single class.

This makes passing them around as a whole easier, and opens a path
to have "generic" filters in form of a lambda or such.

Change-Id: Ibf644b2fedcf0f1a35258030710afff8f5873f88
Reviewed-by: Qt CI Bot <qt_ci_bot@qt-project.org>
Reviewed-by: Eike Ziller <eike.ziller@qt.io>

src/libs/utils/fileutils.h

@@ -82,9 +82,7 @@ public:
     std::function<QString(const FilePath &)> mapToDevicePath;
     std::function<void(const FilePath &,
                        const std::function<bool(const FilePath &)> &, // Abort on 'false' return.
-                       const QStringList &,
-                       QDir::Filters,
-                       QDirIterator::IteratorFlags)> iterateDirectory;
+                       const FileFilter &)> iterateDirectory;
     std::function<QByteArray(const FilePath &, qint64, qint64)> fileContents;
     std::function<bool(const FilePath &, const QByteArray &)> writeFileContents;
     std::function<QDateTime(const FilePath &)> lastModified;