Revert of Wrap ClassLiterals in DoExpressions instead of giving them BlockScopes.

Revert of Wrap ClassLiterals in DoExpressions instead of giving them BlockScopes. (patchset #5 id:80001 of https://codereview.chromium.org/2176653003/ )

Reason for revert:
Blamed for https://bugs.chromium.org/p/chromium/issues/detail?id=716265

Original issue's description:
> Wrap ClassLiterals in DoExpressions instead of giving them BlockScopes.
> 
> This slightly simplifies scope handling. It also makes it possible to
> implement some potential future changes to classes purely in the parser
> by adding additional code to the DoExpression.
> 
> This is a portion of https://codereview.chromium.org/2142333002/, which
> probably isn't going through in full.
> 
> Committed: https://crrev.com/c2bcfc31454bfa95e146cb6002fb6a9a142181f7
> Cr-Commit-Position: refs/heads/master@{#38035}

TBR=adamk@chromium.org,marja@chromium.org,mstarzinger@chromium.org,bakkot@google.com
# Not skipping CQ checks because original CL landed more than 1 days ago.

[Dan Ehrenberg, 2017-04-28 08:33:22]

Created Revert of Wrap ClassLiterals in DoExpressions instead of giving them
BlockScopes.

[Dan Ehrenberg, 2017-04-28 08:33:28]

The CQ bit was checked by littledan@chromium.org to run a CQ dry run

[commit-bot: I haz the power, 2017-04-28 08:33:31]

Dry run: CQ is trying da patch.

Follow status at:
https://chromium-cq-status.appspot.com/v2/patch-status/codereview.chromium.or...

[commit-bot: I haz the power, 2017-04-28 08:35:01]

The CQ bit was unchecked by commit-bot@chromium.org

[commit-bot: I haz the power, 2017-04-28 08:35:02]

Dry run: Try jobs failed on following builders:
  v8_linux64_gyp_rel_ng on master.tryserver.v8 (JOB_FAILED,
http://build.chromium.org/p/tryserver.v8/builders/v8_linux64_gyp_rel_ng/build...)
  v8_linux64_verify_csa_rel_ng on master.tryserver.v8 (JOB_FAILED,
http://build.chromium.org/p/tryserver.v8/builders/v8_linux64_verify_csa_rel_n...)
  v8_linux_mipsel_compile_rel on master.tryserver.v8 (JOB_FAILED,
http://build.chromium.org/p/tryserver.v8/builders/v8_linux_mipsel_compile_rel...)
  v8_linux_nodcheck_rel_ng on master.tryserver.v8 (JOB_FAILED,
http://build.chromium.org/p/tryserver.v8/builders/v8_linux_nodcheck_rel_ng/bu...)
  v8_linux_rel_ng on master.tryserver.v8 (JOB_FAILED,
http://build.chromium.org/p/tryserver.v8/builders/v8_linux_rel_ng/builds/25057)
  v8_presubmit on master.tryserver.v8 (JOB_FAILED,
http://build.chromium.org/p/tryserver.v8/builders/v8_presubmit/builds/40054)

[adamk, 2017-04-28 16:52:27]

This landed a looooong time ago. Not sure a straight revert is a good idea (nor
am I certain that this is better than fixing the underlying issue). Am following
the bug.