We are seeing some web WHOIS HTTP(S) requests made to our endpoints without the Host header specified. This is an error according to the HTTP/1.1 spec. However we do not want to spam our logs with errors that are outside of our control. Do not throw and return a 400 response instead.
Also re-worked the logic a bit to only return HSTS headers if we send a redirect response, not any other error responses. The tests are re-arrange to correspond with the logical flow in the code.
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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=207143230