[fetch] error types too vague for TLS certificate error (#205)

If the JS opens a URL to a server that has a problem with the TLS connection because the server certificate is not signed correctly, the `fetch(...)` method just returns a TypeError

<img width="493" alt="screenshot 2016-01-25 16 05 48" src="https://cloud.githubusercontent.com/assets/124506/12556454/de131d64-c37d-11e5-83cf-b082fbb117b9.png">

It would be useful in this case to have a TLSConnectionError exception, explaining the problem so that JS could at least build an explantation of what went wrong. Perhaps this would allow people to send feedback to the web site owner. It would also allow us to run sites locally for testing and not constantly be wondering why we have problems (I keep jumping around tasks and I keep forgetting this)

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Reply to this email directly or view it on GitHub:
https://github.com/whatwg/fetch/issues/205