Some polyfills do not exist

[doug-wade]

I'm getting the following error:

Unhandled rejection AssertionError [ERR_ASSERTION]: false == true
    at /Users/dwade/foss/koala/node_modules/polyfills/lib/index.js:64:5
    at <anonymous>
    at process._tickCallback (internal/process/next_tick.js:188:7)

Turns out one of the files doesn't exist:

» curl https://raw.githubusercontent.com/axemclion/IndexedDBShim/master/dist/IndexedDBShim.js
404: Not Found