RFR: JDK-8254893: Fix display of search tag results without holder information

[Hannes Wallnöfer]

This is a trivial fix to only display holder information for index items in search results if it is available.

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Commit messages:
 - JDK-8254893: Fix display of search tag results without holder information

Changes: https://git.openjdk.java.net/jdk/pull/1077/files
 Webrev: https://webrevs.openjdk.java.net/?repo=jdk&pr=1077&range=00
  Issue: https://bugs.openjdk.java.net/browse/JDK-8254893
  Stats: 1 line in 1 file changed: 0 ins; 0 del; 1 mod
  Patch: https://git.openjdk.java.net/jdk/pull/1077.diff
  Fetch: git fetch https://git.openjdk.java.net/jdk pull/1077/head:pull/1077

PR: https://git.openjdk.java.net/jdk/pull/1077