[pattern rewriter] Only desugar to call %ToName on computed properties

[pattern rewriter] Only desugar to call %ToName on computed properties

Convert strings to numbers if possible in the runtime call and store
in excluded property list.

BUG=v8:5549
patch from issue 2644723002 at patchset 1 (http://crrev.com/2644723002#ps1)

[Michael Achenbach, 2017-01-19 08:50:47]

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

[commit-bot: I haz the power, 2017-01-19 08:50:50]

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, 2017-01-19 08:52:19]

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

[commit-bot: I haz the power, 2017-01-19 08:52:19]

Dry run: Try jobs failed on following builders:
  v8_linux64_asan_rel_ng on master.tryserver.v8 (JOB_FAILED,
http://build.chromium.org/p/tryserver.v8/builders/v8_linux64_asan_rel_ng/buil...)
  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_rel_ng on master.tryserver.v8 (JOB_FAILED,
http://build.chromium.org/p/tryserver.v8/builders/v8_linux64_rel_ng/builds/19504)
  v8_linux_gcc_compile_rel on master.tryserver.v8 (JOB_FAILED,
http://build.chromium.org/p/tryserver.v8/builders/v8_linux_gcc_compile_rel/bu...)
  v8_win_nosnap_shared_rel_ng on master.tryserver.v8 (JOB_FAILED,
http://build.chromium.org/p/tryserver.v8/builders/v8_win_nosnap_shared_rel_ng...)