[Canvas] `tinymath` preventing Kibana from starting in IE11

[clintandrewhall]

Kibana version: master

Elasticsearch version: snapshot

Server OS version: localhost, MacOS

Browser version: IE11

Browser OS version: Win10

Describe the bug:

Kibana is not running in master in IE11. tinymath is throwing a syntax error originating in Canvas.

Steps to reproduce:

1. yarn start
2. Load localhost in IE11.
3. Observe error

Screenshots (if relevant):

cc: @cqliu1

[elasticmachine]

Pinging @elastic/kibana-canvas