Rendering error in circular text

[jethrogb]

Link to PDF file (or attach file here): https://people.eecs.berkeley.edu/~rsinha/research/pubs/pldi2016.pdf

Configuration:
- Web browser and its version: Firefox 48.0
- Operating system and its version: Arch Linux with FreeType 2.6.5-2
- PDF.js version: Firefox 48.0
- Is an extension: No

Steps to reproduce the problem:
Some of the lettering in the seal on the top right of the first page looks off.

What is the expected behavior? (add screenshot)

This is what it looks like in Okular on the same system and Firefox on Windows.

What went wrong? (add screenshot)

Possible dupe of #2594, but I don't see any errors in the PDFs in that issue.

[Snuffleupagus]

Closing as duplicate of issue #7342.