RFR: JDK-8291734: Return accurate ACC_SUPER access flag for classes

[Joe Darcy]

With the ACC_SUPER information now available from a private getClassAccessFlagsRaw() method, the 
 Set<AccessFlag> accessFlags() 
method can properly model that setting.

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Commit messages:
 - JDK-8291734: Return accurate ACC_SUPER access flag for classes

Changes: https://git.openjdk.org/jdk/pull/9799/files
 Webrev: https://webrevs.openjdk.org/?repo=jdk&pr=9799&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8291734
  Stats: 21 lines in 2 files changed: 2 ins; 5 del; 14 mod
  Patch: https://git.openjdk.org/jdk/pull/9799.diff
  Fetch: git fetch https://git.openjdk.org/jdk pull/9799/head:pull/9799

PR: https://git.openjdk.org/jdk/pull/9799