[es6] Enforce TDZ checks for let/const in StoreLookupSlot

[es6] Enforce TDZ checks for let/const in StoreLookupSlot

With --harmony-sloppy we can get to a runtime store in the presence of
an eval. We therefor need to check that the value is not the hole which
is used to enforce TDZ.

BUG=v8:4284
LOG=N
R=rossberg@chromium.org, littledan@chromium.org

Committed: https://crrev.com/a73338ba9e22c2ac0e2213995849d61a521b8cd0
Cr-Commit-Position: refs/heads/master@{#29577}

[arv (Not doing code reviews), 2015-07-08 19:25:39]

PTAL

[Dan Ehrenberg, 2015-07-09 00:00:47]

https://codereview.chromium.org/1214733013/diff/1/src/runtime/runtime-scopes.cc
File src/runtime/runtime-scopes.cc (right):

https://codereview.chromium.org/1214733013/diff/1/src/runtime/runtime-scopes....
src/runtime/runtime-scopes.cc:1034: }
Looks like this is called by FullCodeGen. Do we need Crankshaft/TF changes?

[arv (Not doing code reviews), 2015-07-09 14:30:36]

https://codereview.chromium.org/1214733013/diff/1/src/runtime/runtime-scopes.cc
File src/runtime/runtime-scopes.cc (right):

https://codereview.chromium.org/1214733013/diff/1/src/runtime/runtime-scopes....
src/runtime/runtime-scopes.cc:1034: }
On 2015/07/09 00:00:47, Dan Ehrenberg wrote:
> Looks like this is called by FullCodeGen. Do we need Crankshaft/TF changes?

TF calls the same runtime function.

Crankshaft bails out on VariableLocation::LOOKUP, as well as on direct eval, so
we are double safe here.

[rossberg, 2015-07-10 11:45:18]

lgtm

[arv (Not doing code reviews), 2015-07-10 15:55:16]

The CQ bit was checked by arv@chromium.org

[commit-bot: I haz the power, 2015-07-10 15:55:31]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1214733013/1

[commit-bot: I haz the power, 2015-07-10 16:20:44]

Committed patchset #1 (id:1)

[commit-bot: I haz the power, 2015-07-10 16:20:59]

Patchset 1 (id:??) landed as
https://crrev.com/a73338ba9e22c2ac0e2213995849d61a521b8cd0
Cr-Commit-Position: refs/heads/master@{#29577}