Disable mangling for SDK browser builds
Disable mangling for SDK browser builds

Summary: Customer ran into an error using the browser build because of a mangling issue. So let's disable it :)

Reviewers: otto

Reviewed By: otto

Subscribers: ben

Differential Revision: https://phabricator.bitgo.com/D7570

BitGo/BitGoJS,BitGo/BitGoJS,BitGo/BitGoJS,BitGo/BitGoJS