by some reason, JDK-8142968 changeset[1] restored WhiteBox in hotspot/test/testlibrary/whitebox while it was moved to test directory in top-level repository long ago by JDK-8067337.
[1] http://hg.openjdk.java.net/jdk9/hs-comp/hotspot/comparison/c558850fac57/test/testlibrary/whitebox/sun/hotspot/WhiteBox.java
[1] http://hg.openjdk.java.net/jdk9/hs-comp/hotspot/comparison/c558850fac57/test/testlibrary/whitebox/sun/hotspot/WhiteBox.java
- duplicates
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                    JDK-8156882 Remove hotspot/test/testlibrary/whitebox -           
- Resolved
 
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- relates to
- 
                    JDK-8156882 Remove hotspot/test/testlibrary/whitebox -           
- Resolved
 
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 P4
  P4