RFR: 8222527: HttpClient doesn't send HOST header when tunelling HTTP/1.1 through http proxy

[Daniel Fuchs]

Hi,

Please find below a fix for:

Issue:
8222527: HttpClient doesn't send HOST header when tunnelling HTTP/1.1
          through http proxy
https://bugs.openjdk.java.net/browse/JDK-8222527

webrev:
http://cr.openjdk.java.net/~dfuchs/webrev_8222527/webrev.00

When sending the internal CONNECT request to the proxy
the stack strips out headers that are destined to the
target host. This fix will ensure that the host header
is not stripped in order to keep conformant with RFC 7230
section 5.4 and RFC 7231 section 4.3.6.

best regards,

-- daniel