Patch Set 7: I would prefer that you didn't submit this

Looks quite good already! I still found some issues:

1. Add some text, then check "Add Signed-off", then check "Compute Change-Id" -> perfect.

2. Add some text, then check "Compute Change-Id", then check "Signed-off" -> extra line break between Change-Id and Singed-off.

3. Add a Commit-Id, then remove it from the text box manually -> The "Compute Change-Id" button remains checked and the Change-Id is created upon commit, but that's probably not what the user would have expected unless they looked at the checkbox really hard...

4. Add some text, then check "Compute Change-Id", then check "Amend previous commit" -> you end up with two Change-Ids in the message (if previous had one); if you then uncheck "Compute Change-Id", only the first one will be removed and the check box will still be selected; if you click the second time, the second Change-Id will be removed and the checkbox unchecked.

I think 2. should be fixed (hopefully not too difficult).

I believe issues 3 and 4 can only be solved if we put the Change-Id in some extra field (similar to Author and Committer) instead of directly editing the message. For the time being, though, I would say the behavior is good enough.