Send appropriate pseudo-headers in HTTP/2 CONNECT request.

Change CreateSpdyHeadersFromHttpRequest() to use the appropriate pseudo-headers
in an HTTP/2 CONNECT request: ":authority" with mandatory port, no ":path", no
":scheme".

BUG=433784

Review URL: https://codereview.chromium.org/1257623004

Cr-Commit-Position: refs/heads/master@{#340872}
5 files changed