Added wxStandardPaths::MSWGetShellDir().

This function allows to get the location of Windows shell special folders not
covered by wxStandardPaths methods (yet), e.g. CSIDL_DESKTOPDIRECTORY.

git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/trunk@61662 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775

include/wx/msw/stdpaths.h

@@ -62,6 +62,10 @@ public:
     // Undo the effects of all preceding IgnoreAppSubDir() calls.
     void DontIgnoreAppSubDir();
 
+
+    // Returns the directory corresponding to the specified Windows shell CSIDL
+    static wxString MSWGetShellDir(int csidl);
+
 protected:
     // get the path corresponding to the given standard CSIDL_XXX constant
     static wxString DoGetDirectory(int csidl);