<i18n dev> RFR: 8305505: NPE in javazic compiler

[Yoshiki Sato]

Please review this PR.  
With this minor change, the javazic compiler (Main.java) can produce the HTML files that display given time zone data correctly.

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Commit messages:
 - Remove trailing spaces
 - Fix a mistake in the change
 - 8305505: NPE in javazic compiler

Changes: https://git.openjdk.org/jdk/pull/13504/files
 Webrev: https://webrevs.openjdk.org/?repo=jdk&pr=13504&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8305505
  Stats: 24 lines in 1 file changed: 9 ins; 6 del; 9 mod
  Patch: https://git.openjdk.org/jdk/pull/13504.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/13504/head:pull/13504

PR: https://git.openjdk.org/jdk/pull/13504