Use GLib to retrieve the pictures directory.

Also remove an unused function.

src/common/helpers.py

@@ -497,19 +497,6 @@ r'Software\Microsoft\Windows\CurrentVersion\Explorer\User Shell Folders')
         win32api.RegCloseKey(rkey)
     return val
 
-def get_my_pictures_path():
-    """
-    Windows-only atm
-    """
-    return get_windows_reg_env('My Pictures')
-
-def get_desktop_path():
-    if os.name == 'nt':
-        path = get_windows_reg_env('Desktop')
-    else:
-        path = os.path.join(os.path.expanduser('~'), 'Desktop')
-    return path
-
 def get_documents_path():
     if os.name == 'nt':
         path = get_windows_reg_env('Personal')

src/dialogs.py

@@ -4960,13 +4960,7 @@ class ImageChooserDialog(FileChooserDialog):
                 else:
                     callback(widget, path_to_file)
 
-        try:
+        path = GLib.get_user_special_dir(GLib.UserDirectory.DIRECTORY_PICTURES)
-            if os.name == 'nt':
-                path = helpers.get_my_pictures_path()
-            else:
-                path = os.environ['HOME']
-        except Exception:
-            path = ''
         FileChooserDialog.__init__(self,
            title_text = _('Choose Image'),
            action = Gtk.FileChooserAction.OPEN,