GUI2: New Folder, File Chooser dialogs

Since I’ve not felt particularly inspired to finish the last two parts of my review of the Under the Burning Suns campaign’s post-quartex (1.3.x - 1.9.x) development history, I suppose I may as well bother my loyal readers with yet another useless report on GUI2 dialog conversions in Wesnoth trunk.<

Okay. I lied. The screenshot above does not come from Wesnoth trunk, but from its fork in a private branch in my local git-svn repository. The component in question is evidently the File Chooser dialog, which is used in the map editor for locating files to open or save, and in the Preferences dialog (and more rarely in the MP menu) for finding the wesnothd or wesnothd.exe MP server binary used to host LAN games.>

I figured that converting the File Chooser to GUI2 will help stomp a few bugs with files whose names look like the obsolete, so-called “WML markup”, and generally make it easier for people to improve it. Once I have reimplemented the current functionality I may look into adding some kind of bookmarks system, or at the very least shortcuts for jumping to directories that are commonly used by both mainline developers and UMC authors.

All this rewriting may also introduce new bugs, of course; hence I’ve not pushed these changes to trunk, even though they are already guarded by the --new-widgets command line switch. I have not pushed them to a public SVN branch either because local Git branches make it much easier to rebase commits against trunk as time goes on.

In the process I found myself in need of converting the New Folder dialog to GUI2 for consistency. Given the sheer size of the C++ code added in the process, I am pretty sure this won’t inconvenience anybody for now — hence I pushed this changeset directly to trunk instead.

(And yes, it should be “New Directory”. I am going to hate myself for the rest of my life for keeping the legacy “user-friendly” terminology that was already in place.)