RFR: 8261010: Delete the Netbeans "default" license header

[Sergey Bylokhov]

Trivial cleanup, the "default" license header is removed in a few components.

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Commit messages:
 - Initial fix

Changes: https://git.openjdk.java.net/jdk/pull/2368/files
 Webrev: https://webrevs.openjdk.java.net/?repo=jdk&pr=2368&range=00
  Issue: https://bugs.openjdk.java.net/browse/JDK-8261010
  Stats: 14 lines in 3 files changed: 0 ins; 14 del; 0 mod
  Patch: https://git.openjdk.java.net/jdk/pull/2368.diff
  Fetch: git fetch https://git.openjdk.java.net/jdk pull/2368/head:pull/2368

PR: https://git.openjdk.java.net/jdk/pull/2368