Fix LT-21976: Merge Create dates when merging entries

[jasonleenaylor]

• Store the date at the start of the import and use it in entry creation. We need to have a consistent date recorded to determine if we read a date from the xml data or not.
• Add a function to return the newest date that was actually read from the xml data.

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This change is 

[github-actions]

LCM Tests

    16 files  ±0      16 suites  ±0   2m 59s ⏱️ +2s
 2 836 tests +1   2 816 ✅ +1   20 💤 ±0  0 ❌ ±0 
11 292 runs  +4  11 124 ✅ +4  168 💤 ±0  0 ❌ ±0 

Results for commit 913b234. ± Comparison against base commit 7120fad.

♻️ This comment has been updated with latest results.

[imnasnainaec]

Reviewable status: 0 of 2 files reviewed, 1 unresolved discussion

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src/SIL.LCModel/Application/ApplicationServices/XmlImportData.cs line 491 at r1 (raw file):

				return;
			}
			if (leNew.DateCreated == m_importDate)

Would it be worth having >= m_importDate on these two checks just in case a .DateCreated is from DateTime.Now on a system with a different clock?

[jasonleenaylor]

src/SIL.LCModel/Application/ApplicationServices/XmlImportData.cs line 491 at r1 (raw file):

Previously, imnasnainaec (D. Ror.) wrote…

Would it be worth having >= m_importDate on these two checks just in case a .DateCreated is from DateTime.Now on a system with a different clock?

No, I don't think it is worth it. The real concern here is retaining data coming in from the import, if we end up with created dates in the future that is a GIGO issue for the user that doesn't cause any real issues for our functionality.

[imnasnainaec]

(but I don't have "Approve" permissions)

Reviewed 1 of 2 files at r1, 1 of 1 files at r6, all commit messages.
Reviewable status: complete! all files reviewed, all discussions resolved (waiting on @jasonleenaylor)

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tests/SIL.LCModel.Tests/Application/ApplicationServices/XmlImportDataTests.cs line 856 at r6 (raw file):

				"</FwDatabase>" + Environment.NewLine
				))
				using(var writer = new StringWriter(sbLog))

(found it!)