Make UBSan happy about OpParameter casts.

Make UBSan happy about OpParameter casts.

R=svenpanne@chromium.org
BUG=chromium:448141
LOG=N

Committed: https://crrev.com/c36b5ac6252ea71701c44a68819f5b96f79b91ed
Cr-Commit-Position: refs/heads/master@{#26042}

[Sven Panne, 2015-01-13 11:01:58]

Using reinterpret_cast doesn't make the underlying problem go away: There is a
mismatch in the equal/hash functions involved. The right kind of fix is probably
similar to
https://codereview.chromium.org/812563002/diff/1/src/compiler/operator.h, at
least we should have a closer look.

[Sven Panne, 2015-01-13 12:52:14]

LGTM. As discussed offline: Let's land it as it is to unblock things, but please
open a v8 bug to fix this and chromium:448100 and chromium:448103 for real (just
assign it to me).

[Michael Starzinger, 2015-01-13 13:01:47]

OK, thanks. I have opened https://code.google.com/p/v8/issues/detail?id=3809 to
keep track of this. Will land this workaround.

[Michael Starzinger, 2015-01-13 13:03:01]

The CQ bit was checked by mstarzinger@chromium.org

[commit-bot: I haz the power, 2015-01-13 13:03:44]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/847093002/20001

[commit-bot: I haz the power, 2015-01-13 13:38:45]

Committed patchset #2 (id:20001)

[commit-bot: I haz the power, 2015-01-13 13:38:57]

Patchset 2 (id:??) landed as
https://crrev.com/c36b5ac6252ea71701c44a68819f5b96f79b91ed
Cr-Commit-Position: refs/heads/master@{#26042}