[release/6.0-rc1] Fix loading app local ICU

[github-actions]

Backport of #57971 to release/6.0-rc1

Fixes #57942

/cc @tarekgh

Customer Impact

Customer reported that when the app opt-in using ICU app-local (feature which uses ICU NuGet package instead of using the system installed ICU libraries) the app crashes.

This regression happened because we have started using a new two ICU APIs and we loaded the pointers of these APIs from a specific ICU library libicui18n. This work with the installed system ICU libraries but didn't work with the ICU comes from the NuGet. Users using ICU app-local with this issue will not be able to start their app.
The fix is just to use the library name libicuuc instead. That will make it work in all scenarios when using the ICU system libraries or when using ICU app-local.

Testing

I have tested this manually with all scenarios when using ICU system libraries and when using ICU app-local. I tested this on Windows and Linux. Also, I have run the whole regression tests with the fix without any problem.

Risk

is very low. we are not changing any real code more than pointing at correct library and we have tested the fix in different environments with different settings.

[ghost]

Tagging subscribers to this area: @tarekgh, @safern
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Issue Details

---

Backport of #57971 to release/6.0-rc1

/cc @tarekgh

Customer Impact

Testing

Risk

Author:	github-actions[bot]
Assignees:	-
Labels:	area-System.Globalization
Milestone:	-

[tarekgh]

CC @danmoseley @ericstj.

I am asking to port it to RC 1 branch. Should I manually port it to RC 2 too?

[danmoseley]

@tarekgh no if it goes into RC1 then it will flow to RC2 automatically.

if we wanted to protect against future bugs like this using automation -- presumably we would need a test project to restore the nuget ICU package? is that a reasonable thing to do?

[danmoseley]

wasm failure is xunit .. #11063

[tarekgh]

@danmoseley

if we wanted to protect against future bugs like this using automation -- presumably we would need a test project to restore the nuget ICU package? is that a reasonable thing to do?

Yes, we already have the issue #35930 tracking this work. @safern is already planning to get it early in 7.0.

[danmoseley]

None of the staging failures are relevant (although, I can't root cause the tvOS crashes, not so many are crashing that it would look like a widespread failure in basic API, as if ICU wouldn't load)

[ViktorHofer]

runtime (Build Browser wasm Release AllSubsets_Mono_RuntimeTests) failure is #11063