Partial Incompatibility with Ember 2.10

[alexlafroscia]

@thoov and I came across a case where ember-block-slots is not compatible with Ember 2.10.0. It seems that yielding a set of arguments to a block slot through block-params, when once of those params is a hash, causes the following issue on browsers that do not have a native WeakMap implementation (yeah, it took a while to get to the bottom of this 😉 )

TypeError: Attempting to define property on object that is not extensible.

I created a demo repo here that reproduces the issue. Basically, run the tests in Phantom and you'll see a failure, but in Chrome you will not. Just running ember test will show a message that isn't helpful, an error about an assertion that is just a symptom of the real problem. If you do ember test --serve you'll see both that error, plus an additional message about the "real" one.

Output from ember test

Output from ember test --serve

[jasonmit]

https://github.com/ciena-blueplanet/ember-block-slots/blob/master/addon/helpers/block-params.js#L27-L31 is likely the cause

Introduced by emberjs/ember.js#14244

[sglanzer-deprecated]

Awesome root cause analysis and thanks a ton for the PR!

[sglanzer-deprecated]

Closed via #44