RFR: 8284894: Fix typos in langtools

[Magnus Ihse Bursie]

I ran `codespell` on the langtools directories, and accepted those changes where it indeed discovered real typos.

(Due to false positives this can unfortunately not be run automatically)

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Commit messages:
 - 8284894: Fix typos in langtools

Changes: https://git.openjdk.java.net/jdk/pull/8251/files
 Webrev: https://webrevs.openjdk.java.net/?repo=jdk&pr=8251&range=00
  Issue: https://bugs.openjdk.java.net/browse/JDK-8284894
  Stats: 17 lines in 10 files changed: 0 ins; 0 del; 17 mod
  Patch: https://git.openjdk.java.net/jdk/pull/8251.diff
  Fetch: git fetch https://git.openjdk.java.net/jdk pull/8251/head:pull/8251

PR: https://git.openjdk.java.net/jdk/pull/8251