RFR: 8201570: Get two bytes for the Linux input event type, not four

[John Neffenger]

Fixes [JDK-8201570](https://bugs.openjdk.java.net/browse/JDK-8201570).

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Commit messages:
 - 8201570: Get two bytes for the Linux input event type, not four

Changes: https://git.openjdk.java.net/jfx/pull/257/files
 Webrev: https://webrevs.openjdk.java.net/jfx/257/webrev.00
  Issue: https://bugs.openjdk.java.net/browse/JDK-8201570
  Stats: 1 line in 1 file changed: 0 ins; 0 del; 1 mod
  Patch: https://git.openjdk.java.net/jfx/pull/257.diff
  Fetch: git fetch https://git.openjdk.java.net/jfx pull/257/head:pull/257

PR: https://git.openjdk.java.net/jfx/pull/257