RFR: 8192931: Regression test java/awt/font/TextLayout/CombiningPerf.java fails

[Phil Race]

As described in the bug evaluation, this test was only useful when it had Lucida Sans as a font in the JDK and
the ICU layout engine. 

I don't think it can be made reliable any more given unknown fonts and the difference in the layput engine.

So delete it.

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Commit messages:
 - 8192931: Regression test java/awt/font/TextLayout/CombiningPerf.java fails

Changes: https://git.openjdk.java.net/jdk/pull/5999/files
 Webrev: https://webrevs.openjdk.java.net/?repo=jdk&pr=5999&range=00
  Issue: https://bugs.openjdk.java.net/browse/JDK-8192931
  Stats: 86 lines in 2 files changed: 0 ins; 86 del; 0 mod
  Patch: https://git.openjdk.java.net/jdk/pull/5999.diff
  Fetch: git fetch https://git.openjdk.java.net/jdk pull/5999/head:pull/5999

PR: https://git.openjdk.java.net/jdk/pull/5999