Enable input context in the file chooser text field.

On Windows, this allows e.g. Cyrillic keyboards to work even if Cyrillic is
not currently the active codepage.

Related issues: fontforge#1729, fontforge#2290

gdraw/gfilechooser.c

@@ -1612,7 +1612,7 @@ static void GFileChooserCreateChildren(GFileChooser *gfc, int flags) {
     boxes[3].creator = GHBoxCreate;
     varray[l++] = &boxes[3];
 
-    gcd[k].gd.flags = gg_visible|gg_enabled;
+    gcd[k].gd.flags = gg_visible|gg_enabled|gg_text_xim;
     gcd[k].gd.handle_controlevent = GFileChooserTextChanged;
     textk = k;
     if ( flags&gg_file_pulldown )