Spike error recovery integration

[chancancode]

[chancancode]

For anyone looking to test this, I pushed these pre-built dist that you can point your package.json at:

before: emberjs/ember.js#spike-error-recovery-integration-dist after: emberjs/ember.js#spike-error-recovery-integration-baseline-dist

[NullVoxPopuli]

Using those branches:

[NullVoxPopuli]

Before proceeding with perf comparisons, we probably need to look in to why the error-recovery assets are 86KB more than the baseline assets