RFR: 8254166: Zero: return-type warning in zeroInterpreter_zero.cpp [v3]

[Aleksey Shipilev]

> This breaks 11u without disabled warnings as errors, but the issue exists in head JDK as well. Might as well fix it
> everywhere.
> Testing:
>   - [x] Linux ARM32 Zero build on HEAD JDK
>   - [x] Linux ARM32 Zero build on 11u

Aleksey Shipilev has updated the pull request with a new target base due to a merge or a rebase. The incremental webrev
excludes the unrelated changes brought in by the merge/rebase. The pull request contains three additional commits since
the last revision:

 - Merge branch 'master' into JDK-8254166-zero-narrow-return
 - Added comment
 - 8254166: Zero: return-type warning in zeroInterpreter_zero.cpp

-------------

Changes:
  - all: https://git.openjdk.java.net/jdk/pull/545/files
  - new: https://git.openjdk.java.net/jdk/pull/545/files/95d62436..2ab022fc

Webrevs:
 - full: https://webrevs.openjdk.java.net/?repo=jdk&pr=545&range=02
 - incr: https://webrevs.openjdk.java.net/?repo=jdk&pr=545&range=01-02

  Stats: 8688 lines in 123 files changed: 4495 ins; 3691 del; 502 mod
  Patch: https://git.openjdk.java.net/jdk/pull/545.diff
  Fetch: git fetch https://git.openjdk.java.net/jdk pull/545/head:pull/545

PR: https://git.openjdk.java.net/jdk/pull/545