Steps to reproduce:

1. Set up a project under VCS (e.g. P4) with at least one asset in it.

2. Make a script that calls EditorUtility.SetDirty() on the asset

3. Call AssetDatabase.SaveAssetIfDirty() on the asset

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Actual results: 
Asset is not checked out in source control

Expected results: 
Asset is checked out in source control

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Reproducible with versions: 
2020.3 onwards (landed in 2022.1, and backported)

Not reproducible with versions: 

Can’t test with versions: 

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Tested on (OS): 
macOS, Windows

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Notes:

•  Can use something like this to test :

{code:c#}
[MenuItem("Test/Test Version Control Checkout")]
private static void TestVersionControlCheckout()
{
var asset = LoadScriptableObject(); // load an asset
asset.stringField += "_NewContent"; // make some changes
EditorUtility.SetDirty(asset);
// AssetDatabase.SaveAssets(); // ok, will checkout the asset
AssetDatabase.SaveAssetIfDirty(asset); // not ok, will not checkout the asset
}
{code}

Originally raised on the forums: https://forum.unity.com/threads/the-version-control-system-wont-checkout-changed-assets-when-using-assetdatabase-saveassetifdirty.1554779/#post-9685544