Remove hacks around checking sync while disposing the shellmap

[abcdefg30]

#19657 made me investigate why those hacks/workarounds are needed. It turns out the sync of the world changes because all actors and effects are dropped from the (shellmap) world when it is being disposed this tick.
This PR comes with three commits:

• We bail early when checking around unsynced code is not enabled, saving us from running the function inside try catch and making the code easier to read imo.
• We no longer trigger an exception when the world is disposing (and thus the sync hash changed). I don't think it makes sense to have a check for sync changes when the world is about to get thrown out anyway.
• We can now remove the HACKs and directly load into the editor.

[pchote]

Nice detective work!

Not tested yet, but changes look sensible.

[pchote]

LGTM and now also tested.

[teinarss]

https://github.com/OpenRA/OpenRA/wiki/Changelog-(bleed)/_compare/e315b6bd3557a53d60feef1a94450fbbd15d9449...97c214b9180f5084887858c09f692c2351eb0188

[anvilvapre]

After disabled the Sync checkboxes in the settings dialog bleed crashes once I deploy my MVC in a Skirmish game. I suspect related to this commit? If i checkout the commit before - no crash.

Exception of type `System.InvalidOperationException`: The current order generator may not be changed from synced code
   at OpenRA.Sync.AssertUnsynced(String message) in /home/taol/source/cs/OpenRA/OpenRA.Game/Sync.cs:line 208
   at OpenRA.World.set_OrderGenerator(IOrderGenerator value) in /home/taol/source/cs/OpenRA/OpenRA.Game/World.cs:line 153
   at OpenRA.Mods.Common.Widgets.WorldInteractionControllerWidget.HandleMouseInput(MouseInput mi) in /home/taol/source/cs/OpenRA/OpenRA.Mods.Common/Widgets/WorldInteractionControllerWidget.cs:line 181
   at OpenRA.Widgets.Ui.HandleInput(MouseInput mi) in /home/taol/source/cs/OpenRA/OpenRA.Game/Widgets/Widget.cs:line 125
   at OpenRA.DefaultInputHandler.<>c__DisplayClass5_0.<OnMouseInput>b__0() in /home/taol/source/cs/OpenRA/OpenRA.Game/Input/InputHandler.cs:line 50
   at OpenRA.DefaultInputHandler.OnMouseInput(MouseInput input) in /home/taol/source/cs/OpenRA/OpenRA.Game/Input/InputHandler.cs:line 51
   at OpenRA.Platforms.Default.Sdl2Input.PumpInput(Sdl2PlatformWindow device, IInputHandler inputHandler, Nullable`1 lockedMousePosition) in /home/taol/source/cs/OpenRA/OpenRA.Platforms.Default/Sdl2Input.cs:line 149
   at OpenRA.Platforms.Default.Sdl2PlatformWindow.PumpInput(IInputHandler inputHandler) in /home/taol/source/cs/OpenRA/OpenRA.Platforms.Default/Sdl2PlatformWindow.cs:line 459
   at OpenRA.Renderer.EndFrame(IInputHandler inputHandler) in /home/taol/source/cs/OpenRA/OpenRA.Game/Renderer.cs:line 312
   at OpenRA.Game.RenderTick() in /home/taol/source/cs/OpenRA/OpenRA.Game/Game.cs:line 728
   at OpenRA.Game.Loop() in /home/taol/source/cs/OpenRA/OpenRA.Game/Game.cs:line 834
   at OpenRA.Game.Run() in /home/taol/source/cs/OpenRA/OpenRA.Game/Game.cs:line 866
   at OpenRA.Game.InitializeAndRun(String[] args) in /home/taol/source/cs/OpenRA/OpenRA.Game/Game.cs:line 295
   at OpenRA.Launcher.Program.Main(String[] args) in /home/taol/source/cs/OpenRA/OpenRA.Launcher/Program.cs:line 32

[anvilvapre]

If you'd like to keep the assertion, perhaps you will want to called RunUnsynched but with the first argument checkSync always to false.

[abcdefg30]

See #19735. I filed #19741 to fix it.