[GEN][ZH] Fix tunnel contain crashes due to uninitialized tunnel systems

[Mauller]

• Fixes: The game crashes when a GLA players surprise attack tunnel gets subdued while deploying and the player surrenders while it is still subdued #1274

This PR fixes various tunnel system related crashes involving the neutral player.

The initial issue was brought up by the replay attached to the associated issue. A players sneak attack tunnel was instantly subdued by a microwave tank, preventing it from fully deploying. This resulted in a crash when the player surrendered.
The tunnel became neutral and the damage being caused by the surrender attempted to retrieve the tunnel system on the neutral player.

The issue is that the neutral player does not have an associated tunnel system.

Other crashes with neutral player tunnels can also occur within kill all contained and other various contain related functions. So i added checks within all of these functions.

A few functions already checked for the presence of a valid player and valid tunnel system on that player, so it seems that it has been an issue in the past for the EA developers.

I also added overrides for some of the functions which were originally being called from the opencontain parent, this was to make it easier to implement the required functionality without adding extra null checks within opencontain.

This Fixes:

• Crash due to the original issue of subdued tunnel deploying and player surrendering
• Crash due to scripts trying to put something into a neutral tunnel
• Crash due to scripts trying to check tunnel contents
• Crash due to neutron shells hitting neutral tunnel
• Crash due to bunker buster hitting neutral tunnel
• Crash due to microwave tanks trying to subdue a neutral tunnel
• Crash due to forcing units to exit a neutral tunnel

[Mauller]

Small change, i initially missed that orderAllPassengersToExit was different in generals compared to zero hour

[xezon]

I remember I also added these null checks a while ago on tunnel crash but then scrapped them when I found the error higher up. In this case, error cannot be fixed higher up?

[Mauller]

In this instance the problem is the neutral player again. And just using normal actions within the game, like those mentioned in the list of crashes this prevents.

The way to properly fix this is to give the neutral player a tunnel system, but its part of the xfercrc so would mismatch the game. Same problems with the player template and other neutral player related issues.

Theres nothing really higher up that can catch the missing tunnel system. And it shouldn't be handled higher up since tunnel systems aren't used beyond tunnel contain.

[Mauller]

Cleaned it up and refactored it a little based on comments

[Mauller]

last push was jsut some small formatting tweaks

[xezon]

How about we simply call the OpenContain::orderAllPassengersToExit here?

After the null check above.

[Mauller]

Yeah that can work, it means the implementation is still left within the open contain variant, we just have a few extra function calls in the end but it should not be a lot of extra overhead.

[Mauller]

Tweaked all the overridden function to call their base opencontain variant instead of reimplementing the internal logic.

[Mauller]

Tweaked and rebased with recent main.

[xezon]

Looks very good.