Default commit message in conflict resolution is reversed

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Summary

When merging two branches with conflicts and resolving those conflicts via the merge request edit, the default commit message is reversed. For example, if I am merging "Development" branch into "master", when resolving the conflict, the commit message defaults to "Merge branch 'master' to 'development'. It should say the inverse.

Steps to reproduce

Create two branches and make conflicting changes to each.
Create a merge request to merge branch 1 to branch 2
In the merge request, click resolve conflicts.
The commit message says the inverse of the merge request merge.

Example Project

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What is the current bug behavior?

Commit message reverses the order of the branches that are being merged.

What is the expected correct behavior?

The commit message should read the branch being merged and the receiving branch in the correct order.

Relevant logs and/or screenshots

Output of checks

Results of GitLab environment info

ENV GitLab EE 9.3.6