RFR: 8269753: Misplaced caret in PatternSyntaxException's detail message

[Ian Graves]

Fixes a bug where carets aren't indented correctly in PatternSyntaxException messages because tab characters are converted to spaces in their indentation.

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Commit messages:
 - 8269753: Misplaced caret in PatternSyntaxException's detail message

Changes: https://git.openjdk.java.net/jdk/pull/4906/files
 Webrev: https://webrevs.openjdk.java.net/?repo=jdk&pr=4906&range=00
  Issue: https://bugs.openjdk.java.net/browse/JDK-8269753
  Stats: 23 lines in 2 files changed: 21 ins; 0 del; 2 mod
  Patch: https://git.openjdk.java.net/jdk/pull/4906.diff
  Fetch: git fetch https://git.openjdk.java.net/jdk pull/4906/head:pull/4906

PR: https://git.openjdk.java.net/jdk/pull/4906