[jfx20] RFR: 8300664 Missing copyright header in ConditionalBinding.java file

[John Hendrikx]

Added a copyright header.

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Commit messages:
 - Add copyright header

Changes: https://git.openjdk.org/jfx/pull/1007/files
 Webrev: https://webrevs.openjdk.org/?repo=jfx&pr=1007&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8300664
  Stats: 25 lines in 1 file changed: 25 ins; 0 del; 0 mod
  Patch: https://git.openjdk.org/jfx/pull/1007.diff
  Fetch: git fetch https://git.openjdk.org/jfx pull/1007/head:pull/1007

PR: https://git.openjdk.org/jfx/pull/1007