Android: Investigate very common crash on exit

[Ghabry]

I can't reproduce this but there are lots of crashes with this stack trace:

Invesitigation hint: Android doesn't shutdown the engine properly. It returns from "main" but when another game is selected it just invokes "main" again without reinitializing static variables.

Cache::System(std::__ndk1::basic_string<char, std::__ndk1::char_traits<char>, 
Cache::SystemOrBlack()+76)
FileRequestAsync::CallListeners(bool)+136)
Game_System::ReloadSystemGraphic()+232)
Player::ResetGameObjects()+16)
Player::Exit()+48)
Player::MainLoop()+548)
Player::Run()+216)