RFR: 7904091: javap report fails if includes interfaces

[Leonid Kuskov]

[CODETOOLS-7904091](https://bugs.openjdk.org/browse/CODETOOLS-7904091): javap report fails if includes interfaces

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Commit messages:
 - CODETOOLS-7904091: javap report fails if includes interfaces

Changes: https://git.openjdk.org/jcov/pull/68/files
  Webrev: https://webrevs.openjdk.org/?repo=jcov&pr=68&range=00
  Issue: https://bugs.openjdk.org/browse/CODETOOLS-7904091
  Stats: 174 lines in 8 files changed: 109 ins; 42 del; 23 mod
  Patch: https://git.openjdk.org/jcov/pull/68.diff
  Fetch: git fetch https://git.openjdk.org/jcov.git pull/68/head:pull/68

PR: https://git.openjdk.org/jcov/pull/68