8272806: [macOS] "Apple AWT Internal Exception" when input method is changed

[prrace]

There's a long eval in the bug report : https://bugs.openjdk.java.net/browse/JDK-8272806 but here's the summary

When focus is lost by the app a message is sent down to native setting a native reference to the input method to null
which is a sort of signal not to notify upwards anything to the input method (which internally will NPE if there's
no focused component as is the case after focus is lost).
But we aren't actually setting it to null because of a check for null which previously checked the wrapper for
the JNI ref was not null but is now obsolete. So just remove the check for null.

The steps to reproduce this bug are very manual and involve installing additional input methods and toggling them
at the system level. So I didn't see a way to write a useful regression test but if you follow the bug report steps you
should be able to verify the fix.

I've run all automated tests just for good measure and they all pass.

---

Progress

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Issue

• JDK-8272806: [macOS] "Apple AWT Internal Exception" when input method is changed

Reviewers

• Sergey Bylokhov (@mrserb - Reviewer)
• Dmitry Markov (@dmarkov20 - Reviewer)
• Alexander Zvegintsev (@azvegint - Reviewer)

Reviewing

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[openjdk]

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[mlbridge]

Webrevs

• 00: Full (f8b42f50)

[openjdk]

@prrace This change now passes all automated pre-integration checks.

ℹ️ This project also has non-automated pre-integration requirements. Please see the file CONTRIBUTING.md for details.

After integration, the commit message for the final commit will be:

8272806: [macOS] "Apple AWT Internal Exception" when input method is changed

Reviewed-by: serb, dmarkov, azvegint

You can use pull request commands such as /summary, /contributor and /issue to adjust it as needed.

At the time when this comment was updated there had been 13 new commits pushed to the master branch:

• 7f80683: 8272783: Epsilon: Refactor tests to improve performance
• 22ef4f0: 5015261: NPE may be thrown if JDesktopIcon is set to null on a JInternalFrame
• 9bc0232: 8269223: -Xcheck:jni WARNINGs working with fonts on Linux
• 2ff4c01: 8271600: C2: CheckCastPP which should closely follow Allocate is sunk of a loop
• ad92033: 8272736: [JVMCI] Add API for reading and writing JVMCI thread locals
• 709b591: 8272553: several hotspot runtime/CommandLine tests don't check exit code
• 1884072: 8265253: javac -Xdoclint:all gives "no comment" warning for code that can't be commented
• 594e516: 8272778: Consolidate is_instance and is_instance_inlined in java_lang_String
• d542745: 8267894: Skip work for empty regions in G1 Full GC
• 741f58c: 8272417: ZGC: fastdebug build crashes when printing ClassLoaderData
• ... and 3 more: https://git.openjdk.java.net/jdk/compare/f77a1a156f3da9068d012d9227c7ee0fee58f571...master

As there are no conflicts, your changes will automatically be rebased on top of these commits when integrating. If you prefer to avoid this automatic rebasing, please check the documentation for the /integrate command for further details.

➡️ To integrate this PR with the above commit message to the master branch, type /integrate in a new comment.

[prrace]

/integrate

[openjdk]

Going to push as commit f681d65.
Since your change was applied there have been 19 commits pushed to the master branch:

• 6e0328f: 8272725: G1: add documentation on needs_remset_update_t vs bool
• 2309b7d: 8253178: Replace LinkedList Impl in net.http.FilterFactory
• 94f5e44: 8271258: @param with non-ascii variable names produces incorrect results
• 7454306: 8272526: Cleanup ThreadStateTransition class
• 0597cde: 8221360: Eliminate Shared_DirtyCardQ_lock
• 928b972: 8271930: Simplify end_card calculation in G1BlockOffsetTablePart::verify
• 7f80683: 8272783: Epsilon: Refactor tests to improve performance
• 22ef4f0: 5015261: NPE may be thrown if JDesktopIcon is set to null on a JInternalFrame
• 9bc0232: 8269223: -Xcheck:jni WARNINGs working with fonts on Linux
• 2ff4c01: 8271600: C2: CheckCastPP which should closely follow Allocate is sunk of a loop
• ... and 9 more: https://git.openjdk.java.net/jdk/compare/f77a1a156f3da9068d012d9227c7ee0fee58f571...master

Your commit was automatically rebased without conflicts.

[openjdk]

@prrace Pushed as commit f681d65.

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