Overhauls `SimpleSSLContext` to remove the need for null checks at the call site, and to accept a key store file search path, which removes the need to copy-paste `SimpleSSLContext` just to change the search path.
### Tips for reviewers 1. Start from `SimpleSSLContext.java` 2. See how `test/jdk/java/net/httpclient/whitebox/java.net.http/jdk/internal/net/http/SimpleSSLContext.java` is renamed to `test/jdk/java/net/httpclient/whitebox/java.net.http/jdk/internal/net/http/SimpleSSLContextWhiteboxAdapter.java` and how `@compile/module=java.net.http .../SimpleSSLContext.java` JTreg tag is used to inject `SimpleSSLContext` ------------- Commit messages: - Overhaul `SimpleSSLContext` and its usages Changes: https://git.openjdk.org/jdk/pull/28765/files Webrev: https://webrevs.openjdk.org/?repo=jdk&pr=28765&range=00 Issue: https://bugs.openjdk.org/browse/JDK-8372661 Stats: 1131 lines in 205 files changed: 83 ins; 712 del; 336 mod Patch: https://git.openjdk.org/jdk/pull/28765.diff Fetch: git fetch https://git.openjdk.org/jdk.git pull/28765/head:pull/28765 PR: https://git.openjdk.org/jdk/pull/28765
