RFR: 8373677: Clear text HttpServer connection could fail fast if receiving SSL ClientHello [v2]

[Daniel Fuchs]

> The first byte of a SSL ClientHello handshake record is 0x16 (22).
> If the first byte received on a HTTP/1.1 clear connection is 0x16, the HTTP server could fail fast, return 400 bad request and immediately close the connection.
> 
> This changeset extends the fail fast behaviour for other ineligible bytes, such as any byte corresponding to ASCII characters <= 31.

Daniel Fuchs has updated the pull request incrementally with one additional commit since the last revision:

  minor test fix - unused import + obsolete comment

-------------

Changes:
  - all: https://git.openjdk.org/jdk/pull/28827/files
  - new: https://git.openjdk.org/jdk/pull/28827/files/d6d11c8c..d7c25539

Webrevs:
 - full: https://webrevs.openjdk.org/?repo=jdk&pr=28827&range=01
 - incr: https://webrevs.openjdk.org/?repo=jdk&pr=28827&range=00-01

  Stats: 3 lines in 1 file changed: 1 ins; 1 del; 1 mod
  Patch: https://git.openjdk.org/jdk/pull/28827.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/28827/head:pull/28827

PR: https://git.openjdk.org/jdk/pull/28827