[es6] Move builtin constructors for primitives to strict mode.

[es6] Move builtin constructors for primitives to strict mode.

The ES6 specification says that "Built-in functions that are ECMAScript
function objects must be strict mode functions", which in particular
means that you can never test for them using the "caller" field of a
sloppy mode function.

CQ_INCLUDE_TRYBOTS=tryserver.v8:v8_linux_layout_dbg,v8_linux_nosnap_dbg
R=mstarzinger@chromium.org
BUG=v8:105
LOG=n

Committed: https://crrev.com/e2f1c26982f57411571c4ce41d02f7d56501b208
Cr-Commit-Position: refs/heads/master@{#30750}

[Michael Starzinger, 2015-09-15 13:09:59]

LGTM with nits.

https://codereview.chromium.org/1347663002/diff/1/src/string.js
File src/string.js (right):

https://codereview.chromium.org/1347663002/diff/1/src/string.js#newcode39
src/string.js:39: "use strict";
nit: Let's add a TODO here that this should at some point be global for the
entire module.

https://codereview.chromium.org/1347663002/diff/1/src/symbol.js
File src/symbol.js (right):

https://codereview.chromium.org/1347663002/diff/1/src/symbol.js#newcode35
src/symbol.js:35: "use strict";
The entire module is already strict, let's drop it.

https://codereview.chromium.org/1347663002/diff/1/src/v8natives.js
File src/v8natives.js (right):

https://codereview.chromium.org/1347663002/diff/1/src/v8natives.js#newcode1344
src/v8natives.js:1344: "use strict";
nit: TODO here as well.

https://codereview.chromium.org/1347663002/diff/1/src/v8natives.js#newcode1394
src/v8natives.js:1394: "use strict";
nit: Likwise.

[Benedikt Meurer, 2015-09-15 13:10:49]

Addressed comments, thanks!

[Benedikt Meurer, 2015-09-15 13:10:53]

The CQ bit was checked by bmeurer@chromium.org

[Benedikt Meurer, 2015-09-15 13:10:53]

The patchset sent to the CQ was uploaded after l-g-t-m from
mstarzinger@chromium.org
Link to the patchset: https://codereview.chromium.org/1347663002/#ps20001
(title: "Address Michi's comments")

[commit-bot: I haz the power, 2015-09-15 13:11:05]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1347663002/20001
View timeline at
 https://chromium-cq-status.appspot.com/patch-timeline/1347663002/20001

[commit-bot: I haz the power, 2015-09-15 14:32:31]

Committed patchset #2 (id:20001)

[commit-bot: I haz the power, 2015-09-15 14:32:50]

Patchset 2 (id:??) landed as
https://crrev.com/e2f1c26982f57411571c4ce41d02f7d56501b208
Cr-Commit-Position: refs/heads/master@{#30750}