(svn r3235) - Fix: fix two crashes, one with making a screenshot in the main menu without any game loaded, another when failing to load a scenario in 'New Game'

openttd.c

@@ -778,7 +778,6 @@ void SwitchMode(int new_mode)
 	case SM_LOAD: { /* Load game, Play Scenario */
 		_opt_ptr = &_opt;
 
-		_error_message = INVALID_STRING_ID;
 		if (!SafeSaveOrLoad(_file_to_saveload.name, _file_to_saveload.mode, GM_NORMAL)) {
 			LoadIntroGame();
 			ShowErrorMessage(_error_message, STR_4009_GAME_LOAD_FAILED, 0, 0);

screenshot.c

@@ -483,7 +483,7 @@ static char *MakeScreenshotName(const char *ext)
 	char *base;
 	int serial;
 
-	if (_game_mode == GM_EDITOR || _local_player == OWNER_SPECTATOR) {
+	if (_game_mode == GM_EDITOR || _game_mode == GM_MENU || _local_player == OWNER_SPECTATOR) {
 		sprintf(_screenshot_name, "screenshot");
 	} else {
 		const Player* p = GetPlayer(_local_player);