Branch and Pull request side by side diff view is showing multiple "undefined" string

Issue Summary

Side by side diff on a branch
Branch side by side diff view is showing multiple "undefined" strings. These "undefined" strings are not part of the file being viewed.

Side by side diff in pull request creation
The side by side diff view when creating a pull request also contains multiple "undefined" strings. These "undefined" strings are not part of the file being viewed.

Steps to Reproduce

Side by side diff on a branch

1. View the branch diff in side by side diff view

Side by side diff in pull request creation
1. Create a pull request
2. Click "Diff" to to see the diff
3. Click the "Side-by-side" button.
3. "Undefined" appears on lines, normally near the bottom of the file, regardless of blank lines or anything else.

Expected Results

The branch side by side diff view should display the correct diff

Actual Results

The branch side by side diff view display multiple "undefined" string along with the file diff

Workaround

Use the normal branch diff view