Use -O3 instead of -O

[ry]

Attempting to correct hyper_hello latency problem.

[hayd]

Huh, this failed when I tried it locally!

Edit: maybe args += [ "-C", "debuginfo=0", "-C", "opt-level=3" ] ?

It wasn't clear to me if this actually affected hyper_hello as the size remained the same :/

[hayd]

Does this definitely apply to the hyper_hello binary?

[ry]

Yes rather sure

[ry]

I think this is a good line of reasoning tho... We should compare cargo built hyper_hello vs gn built hyper_hello and see if there's a difference. (Unfortunately at the moment I can't repeat the latency slowness locally - only on travis.)

[hayd]

Can we push the binary somewhere/inspect what travis is building?
That way we can compare gn built hyper_hello vs cargo/rustc built. If they're the same size we can be pretty sure they're built with the same flags...

I was wondering if the is_official block could be an else block after is_debug (though it doesn't seem to make a difference to the hyper_hello binary either.)