Fix line commenting for the initial commit
What does this MR do?
Support line positions on the initial commit, where we can't compare because there's no parent commit.
Are there points in the code the reviewer needs to double check?
I chose to use the blank SHA to represent the initial commit, but it could as easily be the same SHA. I just thought this was clearer.
Why was this MR needed?
People couldn't add line comments to the initial commit!
What are the relevant issue numbers?
Closes #20895 (closed).
Screenshots (if relevant)
Does this MR meet the acceptance criteria?
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CHANGELOG entry added (N/A, regression) -
Documentation created/updated (N/A) -
API support added (N/A) - Tests
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Added for this feature/bug -
All builds are passing
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Conform by the style guides -
Branch has no merge conflicts with master
(if you do - rebase it please) -
Squashed related commits together