Avoid multiple rewriting of object key expressions

Avoid multiple rewriting of object key expressions

NonPatternRewrite was called more than once for the same AST
in the case of (computed) key expressions present in object
literals.  As an example, in:

   var x = { [[...42]]: 17 };

the array containing the spread would be desugared first and
then the resulting do-expression would again be desugared.

This could be problematic if a computed key expression contains
large nested array/object literals.

R=rossberg@chromium.org
BUG=

Committed: https://crrev.com/077d70f0fe594151f7b28ea0c81aa0dfa3af8d52
Cr-Commit-Position: refs/heads/master@{#33632}

[rossberg, 2016-01-29 19:38:21]

lgtm

[nickie, 2016-02-01 08:48:40]

The CQ bit was checked by nikolaos@chromium.org

[commit-bot: I haz the power, 2016-02-01 08:48:47]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1645023002/1
View timeline at
 https://chromium-cq-status.appspot.com/patch-timeline/1645023002/1

[commit-bot: I haz the power, 2016-02-01 09:18:16]

Committed patchset #1 (id:1)

[commit-bot: I haz the power, 2016-02-01 09:18:47]

Description was changed from

==========
Avoid multiple rewriting of object key expressions

NonPatternRewrite was called more than once for the same AST
in the case of (computed) key expressions present in object
literals.  As an example, in:

   var x = { [[...42]]: 17 };

the array containing the spread would be desugared first and
then the resulting do-expression would again be desugared.

This could be problematic if a computed key expression contains
large nested array/object literals.

R=rossberg@chromium.org
BUG=
==========

to

==========
Avoid multiple rewriting of object key expressions

NonPatternRewrite was called more than once for the same AST
in the case of (computed) key expressions present in object
literals.  As an example, in:

   var x = { [[...42]]: 17 };

the array containing the spread would be desugared first and
then the resulting do-expression would again be desugared.

This could be problematic if a computed key expression contains
large nested array/object literals.

R=rossberg@chromium.org
BUG=

Committed: https://crrev.com/077d70f0fe594151f7b28ea0c81aa0dfa3af8d52
Cr-Commit-Position: refs/heads/master@{#33632}
==========

[commit-bot: I haz the power, 2016-02-01 09:18:47]

Patchset 1 (id:??) landed as
https://crrev.com/077d70f0fe594151f7b28ea0c81aa0dfa3af8d52
Cr-Commit-Position: refs/heads/master@{#33632}