[turbofan] Always check that we make progress in the Typer.

[turbofan] Always check that we make progress in the Typer.

Turn the DCHECK in the Typer into a CHECK, and don't silently continue
in production. This way we know that we will always make progress
towards the fixpoint.

R=jarin@chromium.org, rossberg@chromium.org

Committed: https://crrev.com/16053273bfec561ee56226588ffe58912469f587
Cr-Commit-Position: refs/heads/master@{#31568}

[Benedikt Meurer, 2015-10-26 13:14:26]

Hey Jaro, Andreas,

Kill all the defensive programming in TurboFan!
Please take a look.

Thanks,
Benedikt

[rossberg, 2015-10-26 13:15:54]

LGTM, but does this actually hold? :)

[Benedikt Meurer, 2015-10-26 13:16:45]

On 2015/10/26 13:15:54, rossberg wrote:
> LGTM, but does this actually hold? :)

Well, if it doesn't, then we have a bug (that was hidden so far).

[Jarin, 2015-10-26 13:17:36]

Yes! lgtm.

[Benedikt Meurer, 2015-10-26 13:17:45]

The CQ bit was checked by bmeurer@chromium.org

[commit-bot: I haz the power, 2015-10-26 13:17:54]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1422893003/1
View timeline at
 https://chromium-cq-status.appspot.com/patch-timeline/1422893003/1

[commit-bot: I haz the power, 2015-10-26 14:07:21]

Committed patchset #1 (id:1)

[commit-bot: I haz the power, 2015-10-26 14:07:48]

Patchset 1 (id:??) landed as
https://crrev.com/16053273bfec561ee56226588ffe58912469f587
Cr-Commit-Position: refs/heads/master@{#31568}