Handle Chinese autonyms explicitly in IetfLanguageTag

[StephenMcConnel]

This fixes a bug reported in Bloom (BL-15436)

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This change is 

[github-actions]

Palaso Tests

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Results for commit 02628e5. ± Comparison against base commit dce7400.

This pull request skips 1 test.

SIL.Tests.IO.FileLocationUtilitiesTests ‑ LocateInProgramFiles_SendValidProgramDeepSearch_ReturnsProgramPath

[imnasnainaec]

@imnasnainaec reviewed 1 of 2 files at r1, all commit messages.
Reviewable status: 1 of 2 files reviewed, 1 unresolved discussion

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SIL.WritingSystems/IetfLanguageTag.cs line 1328 at r1 (raw file):

			{
				return kTraditionalChineseAutonym;
			}

What about the (generalCode == ChineseSimplifiedTag && uiLanguageTag == ChineseTraditionalTag) and (generalCode == ChineseTraditionalTag && uiLanguageTag == ChineseSimplifiedTag) cases?

[StephenMcConnel]

Reviewable status: 1 of 2 files reviewed, 1 unresolved discussion (waiting on @imnasnainaec)

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SIL.WritingSystems/IetfLanguageTag.cs line 1328 at r1 (raw file):

Previously, imnasnainaec (D. Ror.) wrote…

What about the (generalCode == ChineseSimplifiedTag && uiLanguageTag == ChineseTraditionalTag) and (generalCode == ChineseTraditionalTag && uiLanguageTag == ChineseSimplifiedTag) cases?

I have no idea what the logograms would be in the mixed code situations that you describe. That's why I stuck to the pure autonym assignments. If you know that the logograms would be the same regardless of the specific uiLanguageTag, I'd be happy to change the code.

[imnasnainaec]

Reviewable status: 1 of 2 files reviewed, 1 unresolved discussion (waiting on @StephenMcConnel)

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SIL.WritingSystems/IetfLanguageTag.cs line 1328 at r1 (raw file):

Previously, StephenMcConnel (Steve McConnel) wrote…

I have no idea what the logograms would be in the mixed code situations that you describe. That's why I stuck to the pure autonym assignments. If you know that the logograms would be the same regardless of the specific uiLanguageTag, I'd be happy to change the code.

I just noticed that GetLanguagePart will return zh and neither ChineseSimplifiedTag nor ChineseTraditionalTag, so the two new cases are currently never met.

I think it would be safe to go with

			else if (generalCode == ChineseSimplifiedTag && uiLanguageTag == "zh")
			{
				// Chinese autonyms are also messed up in various ways, so we hard-code them here.
				return kSimplifiedChineseAutonym;
			}
			else if (generalCode == ChineseTraditionalTag && uiLanguageTag == "zh")
			{
				return kTraditionalChineseAutonym;
			}

[StephenMcConnel]

I've decided to let Noel fix this problem since she has a better grasp on the issues.

[nabalone]

Replaced with #1477