Set content-length for clients, who don't understand chunked

[makhov]

For example, Android emulator can't work with Transfer-Encoding: chunked and it's very annoying to me.

[elazarl]

Hi,

Thanks for the PR.

This is problematic for big requests that won't fit the memory.

Do you have a suggestion what to do?

Maybe we can write a RequestHandler for Android that does just that?

(Apologies for the delay)

[2tvenom]

@makhov thank you! this is work with android devices