RFR: 7903269: jextract test failures after Layout updates change

Mon Aug 29 10:26:39 UTC 2022

Missed isStruct, isUnion changes in tests

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Commit messages:
 - 7903269: jextract test failures after Layout updates change

Changes: https://git.openjdk.org/jextract/pull/64/files
 Webrev: https://webrevs.openjdk.org/?repo=jextract&pr=64&range=00
  Issue: https://bugs.openjdk.org/browse/CODETOOLS-7903269
  Stats: 11 lines in 3 files changed: 4 ins; 0 del; 7 mod
  Patch: https://git.openjdk.org/jextract/pull/64.diff
  Fetch: git fetch https://git.openjdk.org/jextract pull/64/head:pull/64

PR: https://git.openjdk.org/jextract/pull/64