Following the guideline of the last comment on [JDK-8349670](https://bugs.openjdk.org/browse/JDK-8349670?focusedId=14794649&page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel#comment-14794649), resolves the issue where sending a 1xx status code would close the input stream, preventing the server from reading the body.
- Adds a new flag checking if the incoming request is an upgrade request. - When receiving an upgrade request, directly return the input/output stream - When a 1xx status code is sent by `sendResponseHeaders`, the input/output streams will not be closed prematurely. - sentHeaders will not be set to true when sending 1xx status codes ------------- Commit messages: - Merge branch 'openjdk:master' into JDK-8349670 - Update InputRead1xxTest.java - Update InputRead1xxTest.java - support all 1xx - Create InputRead101Test.java - Send interim responses for 101 upgrade requests Changes: https://git.openjdk.org/jdk/pull/27069/files Webrev: https://webrevs.openjdk.org/?repo=jdk&pr=27069&range=00 Issue: https://bugs.openjdk.org/browse/JDK-8349670 Stats: 317 lines in 2 files changed: 293 ins; 0 del; 24 mod Patch: https://git.openjdk.org/jdk/pull/27069.diff Fetch: git fetch https://git.openjdk.org/jdk.git pull/27069/head:pull/27069 PR: https://git.openjdk.org/jdk/pull/27069
