update brand.js

[iamayushdas]

I understand that:

• I'm submitting this PR for reference only. It shows an example of what I'd like to see changed but
  I understand that it will not be merged and I will not be listed as a contributor on this project.

[tagliala]

Hi,

thanks for this PR.

This file is being generated by our build system, could you please provide the differences between the two approaches?

[iamayushdas]

Hi,

thanks for this PR.

This file is being generated by our build system, could you please provide the differences between the two approaches?

I have used arrow function in my edition which was not there earlier.

[kamerat]

This will break the whole file.
The correct IIFE with arrow function would be:

(() => {
  /* */
})()