Function scopes only must have a context if they call sloppy eval

Function scopes only must have a context if they call sloppy eval

A strict arrow function with no parameters and no variable bindings
won't need a context object because it will never have any
locals.  (This is unlike strict normal functions, which do have
"arguments" and "this" locals.)

R=rossberg@chromium.org
BUG=v8:4056
LOG=N

Committed: https://crrev.com/d5fd58165c5348c45e3a63d60df9d75787b44e83
Cr-Commit-Position: refs/heads/master@{#28031}

[rossberg, 2015-04-23 11:54:11]

lgtm

[wingo, 2015-04-23 12:06:33]

The CQ bit was checked by wingo@igalia.com

[commit-bot: I haz the power, 2015-04-23 12:06:48]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1093183003/1

[wingo, 2015-04-23 12:26:08]

On 2015/04/23 12:06:48, I haz the power (commit-bot) wrote:
> CQ is trying da patch. Follow status at
>  https://chromium-cq-status.appspot.com/patch-status/1093183003/1

Bah.  Apologies for not running this one under debug mode, I'm an idiot.

[commit-bot: I haz the power, 2015-04-23 12:31:46]

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

[commit-bot: I haz the power, 2015-04-23 12:31:47]

Try jobs failed on following builders:
  v8_linux_arm64_rel on tryserver.v8 (JOB_FAILED,
http://build.chromium.org/p/tryserver.v8/builders/v8_linux_arm64_rel/builds/5093)

[wingo, 2015-04-23 12:47:04]

On 2015/04/23 12:31:47, I haz the power (commit-bot) wrote:
> Try jobs failed on following builders:
>   v8_linux_arm64_rel on tryserver.v8 (JOB_FAILED,
>
http://build.chromium.org/p/tryserver.v8/builders/v8_linux_arm64_rel/builds/5093)

Update fixes this failure (which only occurred in the newly added test).

[rossberg, 2015-04-23 12:56:12]

lgtm

[wingo, 2015-04-23 12:56:55]

The CQ bit was checked by wingo@igalia.com

[commit-bot: I haz the power, 2015-04-23 12:57:17]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1093183003/20001

[commit-bot: I haz the power, 2015-04-23 13:20:15]

Committed patchset #2 (id:20001)

[commit-bot: I haz the power, 2015-04-23 13:20:32]

Patchset 2 (id:??) landed as
https://crrev.com/d5fd58165c5348c45e3a63d60df9d75787b44e83
Cr-Commit-Position: refs/heads/master@{#28031}