RFR: 8289559 : java/awt/a11y/AccessibleJPopupMenuTest.java test fails with java.lang.NullPointerException

[lawrence.andrews]

Fixed the java.lang.NullPointerException & tested .

@shurymury

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Commit messages:
 - 8289559 : java/awt/a11y/AccessibleJPopupMenuTest.java test fails with java.lang.NullPointerException

Changes: https://git.openjdk.org/jdk/pull/9342/files
 Webrev: https://webrevs.openjdk.org/?repo=jdk&pr=9342&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8289559
  Stats: 1 line in 1 file changed: 0 ins; 0 del; 1 mod
  Patch: https://git.openjdk.org/jdk/pull/9342.diff
  Fetch: git fetch https://git.openjdk.org/jdk pull/9342/head:pull/9342

PR: https://git.openjdk.org/jdk/pull/9342