Issue #379: "Windowed Mode" doesn't remember maximize state in multi-window mode

This patch (created by Michael Henning) attempts to resolve the second half of #379.

The original fix allowed single window mode to remember it had been maximized on start. The follow-up patch extended this to multi-window mode as well. The only required change was to remove the sessionrc-expected-2-6 test code as it no longer exists.