RFR: 8252689: Classes are loaded from jrt:/java.base even when CDS is used

[Yumin Qi]

Java.util.jar.Manifest related classes not archived since they are neither in classlist or loaded in dump process.
Manually create a dummy Manifest object will cause those classes loaded in dump and archived.

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Commit messages:
 - 8252689: Classes are loaded from jrt:/java.base even when CDS is used

Changes: https://git.openjdk.java.net/jdk/pull/134/files
 Webrev: https://webrevs.openjdk.java.net/?repo=jdk&pr=134&range=00
  Issue: https://bugs.openjdk.java.net/browse/JDK-8252689
  Stats: 34 lines in 3 files changed: 19 ins; 13 del; 2 mod
  Patch: https://git.openjdk.java.net/jdk/pull/134.diff
  Fetch: git fetch https://git.openjdk.java.net/jdk pull/134/head:pull/134

PR: https://git.openjdk.java.net/jdk/pull/134