event/TimerList: Add custom compare for android

[DDRBoxman]

NDK doesn't seem to support using std::compare_three_way for time_point so this implements that.

[DDRBoxman]

Interesting looks like macOS is failing on std::compare_three_way missing too 🤔

[MaxKellermann]

Interesting looks like macOS is failing on std::compare_three_way missing too 🤔

It's because both Android NDK and macOS ship with an outdated libc++ version which didn't implement this part of C++20.

I don't like this PR because it adds code noise to all platforms, even those that are standards-compliant. At least this should be #ifed and come with a proper explanatory comment. But I guess we could just as well wait for NDK r27 which should be here any day now.

(I don't care for macOS. It's a broken platform with a broken toolchain.)

[DDRBoxman]

I'm fine with waiting for r27 instead

[MaxKellermann]

r27-beta1 is out: https://dl.google.com/android/repository/android-ndk-r27-beta1-linux.zip
(I havn't yet tested whether this release fixes the libc++ bug.)

[MaxKellermann]

Now tested. NDK r27-beta1 has the fix for this C++20 bug.