RFR: 8289427: compiler/compilercontrol/jcmd/ClearDirectivesFileStackTest.java failed with null setting

[KIRIYAMA Takuya]

The problem of JDK-8289427 is caused by using incorrect compiler settings when the auto generated INTRINSIC parameter is null.
I fixed it to use the appropriate value if the argument of cmd was null.
Please review this change.

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Commit messages:
 - 8289427: compiler/compilercontrol/jcmd/ClearDirectivesFileStackTest.java failed with null setting

Changes: https://git.openjdk.org/jdk/pull/9318/files
 Webrev: https://webrevs.openjdk.org/?repo=jdk&pr=9318&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8289427
  Stats: 3 lines in 2 files changed: 0 ins; 1 del; 2 mod
  Patch: https://git.openjdk.org/jdk/pull/9318.diff
  Fetch: git fetch https://git.openjdk.org/jdk pull/9318/head:pull/9318

PR: https://git.openjdk.org/jdk/pull/9318