Issue with polyfills

I'm not sure if it is a karma-coverage or Istanbul issue, but it seems using polyfills that change primitive prototypes or some properties on the global object make karma unit-tests fail in a very obscure way.

It took me a lot of digging to come to this conclusion, as the error manifests itself with all tests failing and messages that look like

```
Error: [$injector:unpr] Unknown provider:
http://errors.angularjs.org/1.2.28/$injector/unpr?p0=
```

Usually when angular complains about an Unknown provider, it states the (sometimes obfuscated) name of the missing provider, but here we just have "Unknown provider:" with no name and a huge url encoded stack that doesn't help at all.

I suspect it might be more of a karma-coverage than Istanbul issue because the polyfill file is not supposed to get instrumented in my setup, but I saw two cases:
- one polyfill file that can be loaded but will generate the issue when included in the "coverage" preprocessor glob target (excluding it from preprocessing prevents the errors)
- one polyfill that will generate the errors even if it isn't included in the "coverage" preprocessor glob for instrumentation.

Start by reproducing the failure with the two polyfill cases described: one included in the coverage preprocessor glob and one excluded from it. Compare Karma coverage and Istanbul behavior, using the AngularJS unknown-provider output to identify where the failure begins. Done means the responsible component and a reproducible cause are established.

Written by the indexing model from the issue text.