Strict types indicator in backtraces

Hi all,

I've written a small patch to add a "strict_types" key to the backtrace
information for functions.

https://github.com/php/php-src/pull/2177

The idea here is to be able to see more easily whether a parameter may have
had it's type changed or not during a trace.

Thoughts and opinions?

I'm not sure I understand what the intended use case here is. Can you maybe
show an example of where this would be useful / how it would be used?

Note that the parameter type may change even with strict_types
(int->float). Further note that parameter values may change in the body of
the function, so you don't have a guarantee that it's the original value in
any case.

Thanks,
Nikita