Editor: Use native separators in the search/directory input

This is called for example with the "Find in This Directory..."
action in the project tree.

Change-Id: If4c523e9f416b241b4ac7057d2dd11821af2c990
Reviewed-by: Eike Ziller <eike.ziller@digia.com>

src/plugins/texteditor/findinfiles.cpp

@@ -186,7 +186,7 @@ void FindInFiles::readSettings(QSettings *settings)
 
 void FindInFiles::setDirectory(const QString &directory)
 {
-    syncComboWithSettings(m_directory, directory);
+    syncComboWithSettings(m_directory, QDir::toNativeSeparators(directory));
 }
 
 void FindInFiles::findOnFileSystem(const QString &path)