Bugfix: Correctly return to initial state after prev/next/back_and_forth (Thanks Brian)

Fixes: #552

testcases/t/179-regress-multiple-ws.t

@@ -0,0 +1,25 @@
+#!perl
+# vim:ts=4:sw=4:expandtab
+#
+# The command "move workspace prev; workspace prev" will lead to an error.
+# This regression is present in 7f9b65f6a752e454c492447be4e21e2ee8faf8fd
+use i3test;
+
+my $i3 = i3(get_socket_path());
+
+# Open one workspace to move the con to
+my $old = fresh_workspace;
+my $keep_open_con = open_empty_con($i3);
+
+# Get a workspace and open a container
+my $tmp = fresh_workspace;
+my $con = open_empty_con($i3);
+
+is(@{get_ws_content($tmp)}, 1, 'one container');
+is(@{get_ws_content($old)}, 1, 'one container on old ws');
+
+cmd 'move workspace prev; workspace prev';
+
+is(@{get_ws_content($old)}, 2, 'container moved away');
+
+done_testing;