RFR: 7266: Context Switch event handling breaks if JMC has old and new types parsed simultaneously

[Henrik Dafgård]

Follow up PR to fix incorrect synthetic attribute ID.

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Commit messages:
 - Fix formatting
 - Fix context switch attribute id

Changes: https://git.openjdk.java.net/jmc/pull/263/files
 Webrev: https://webrevs.openjdk.java.net/?repo=jmc&pr=263&range=00
  Issue: https://bugs.openjdk.java.net/browse/JMC-7266
  Stats: 10 lines in 1 file changed: 1 ins; 0 del; 9 mod
  Patch: https://git.openjdk.java.net/jmc/pull/263.diff
  Fetch: git fetch https://git.openjdk.java.net/jmc pull/263/head:pull/263

PR: https://git.openjdk.java.net/jmc/pull/263