Patch Set 7: Looks good to me, but someone else must approve

I found no issues with the old commit dialog.

I found some issues with the new commit functionality in the staging view which could be fixed later on:

** Checkbox selection is lost on repo change
- check checkboxes "Add Change-ID"  and "Add Signed-Off-by"
- select change from other repo
- select change from initial repo
-> Checkboxes are unselected. Selecting "Add Signed-Off-by" creates an additional Signed-Off-by-line

** Commit is enabled for empty "Staged Changes" list
This creates an empty commit

** Amend should be disabled for a merge commit, as in native git

** # WARNING: head commit changed in the meantime does only appear if I change the repo selection
- make a change
- select amend in the staging view
- reset soft to the previous commit
- no warning appears
- change repo selection and back
- now the warning appears
-> it should appear directly after reset
However, this may work with change 3562