RFR: 8321540: ClassSignature.parseFrom() throws StringIndexOutOfBoundsException for invalid signatures

[Adam Sotona]

ClassFile API models and parses signatures, however parsing of the signatures mostly throws IIOBE when it fails.
This patch improves SignaturesImpl parsing methods implementation and errors handling and adds relevant negative tests.
The parser is not an ultimate signatures validator yet, however this is a step forward to it.

Please review.

Thanks,
Adam

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Commit messages:
 - 8321540: ClassSignature.parseFrom() throws StringIndexOutOfBoundsException for invalid signatures

Changes: https://git.openjdk.org/jdk/pull/17058/files
 Webrev: https://webrevs.openjdk.org/?repo=jdk&pr=17058&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8321540
  Stats: 134 lines in 2 files changed: 103 ins; 5 del; 26 mod
  Patch: https://git.openjdk.org/jdk/pull/17058.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/17058/head:pull/17058

PR: https://git.openjdk.org/jdk/pull/17058