Sass error in ionic.functions.scss after upgrading Ionic/Angular

I upgraded to Ionic 3.7.1 and Angular to 4.4.3, deleted and installed npm_modules and get a runtime error in the sass compiling.
Anyone have any ideas on how to address this?

B5A59301-4549-437A-9EEB-6C5568C20FFA

@heycoach Can you please post how are you calling the method str-index?

I am not calling the method, it is part of the "ionic cordova build ios ", I believe it is part of the sass compilation to css

For now, please comment out the line 202 as in the screenshot in file
ionic-angular/themes/ionic.mixins.scss

till the issue is resolved by Ionic team.

@heycoach let me know if this worked for you.

Thanks, that does work if I set $viewBox: null;
A temporary solution that I hope will have a more permanent solution.