There is an updated pull request by pbui against master on the void-packages repository

https://github.com/pbui/void-packages chromium
https://github.com/void-linux/void-packages/pull/16037

chromium: update to 78.0.3904.87.
- Addresses CVE-2019-13721, CVE-2019-13720:

    https://chromereleases.googleblog.com/2019/10/stable-channel-update-for-desktop_31.html

- Built for x86_64, i686, x86_64.
- Tested on x86_64.

A patch file from https://github.com/void-linux/void-packages/pull/16037.patch is attached