Restore per-TypedArray-class length accessors as a perf workaround

Restore per-TypedArray-class length accessors as a perf workaround

This patch is a workaround to the performance regression caused by
implementing the ES2015 TypedArray prototype chain: Include a
per-TypedArray-subclass length getter so that the superclass getter does
not become polymorphic. The patch appears to fix a regression in the
Gameboy Octane benchmark.

BUG=chromium:579905
R=adamk
LOG=Y

Committed: https://crrev.com/03ce7711e474a0ef74f723b30ae1527c89dec010
Cr-Commit-Position: refs/heads/master@{#33501}

[Dan Ehrenberg, 2016-01-25 19:00:25]

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

[commit-bot: I haz the power, 2016-01-25 19:00:34]

Dry run: CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1624383003/1
View timeline at
 https://chromium-cq-status.appspot.com/patch-timeline/1624383003/1

[adamk, 2016-01-25 19:21:22]

lgtm % one more TODO

https://codereview.chromium.org/1624383003/diff/1/src/js/typedarray.js
File src/js/typedarray.js (right):

https://codereview.chromium.org/1624383003/diff/1/src/js/typedarray.js#newcod...
src/js/typedarray.js:839: utils.InstallGetter(GlobalNAME.prototype, "length",
NAME_GetLength,
Please add a comment here too.

[commit-bot: I haz the power, 2016-01-25 19:44:08]

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

[commit-bot: I haz the power, 2016-01-25 19:44:09]

Dry run: This issue passed the CQ dry run.

[Dan Ehrenberg, 2016-01-25 20:04:59]

The CQ bit was checked by littledan@chromium.org

[Dan Ehrenberg, 2016-01-25 20:04:59]

The patchset sent to the CQ was uploaded after l-g-t-m from adamk@chromium.org
Link to the patchset: https://codereview.chromium.org/1624383003/#ps20001
(title: "More TODOs")

[commit-bot: I haz the power, 2016-01-25 20:05:03]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1624383003/20001
View timeline at
 https://chromium-cq-status.appspot.com/patch-timeline/1624383003/20001

[commit-bot: I haz the power, 2016-01-25 20:25:41]

Committed patchset #2 (id:20001)

[commit-bot: I haz the power, 2016-01-25 20:26:54]

Description was changed from

==========
Restore per-TypedArray-class length accessors as a perf workaround

This patch is a workaround to the performance regression caused by
implementing the ES2015 TypedArray prototype chain: Include a
per-TypedArray-subclass length getter so that the superclass getter does
not become polymorphic. The patch appears to fix a regression in the
Gameboy Octane benchmark.

BUG=chromium:579905
R=adamk
LOG=Y
==========

to

==========
Restore per-TypedArray-class length accessors as a perf workaround

This patch is a workaround to the performance regression caused by
implementing the ES2015 TypedArray prototype chain: Include a
per-TypedArray-subclass length getter so that the superclass getter does
not become polymorphic. The patch appears to fix a regression in the
Gameboy Octane benchmark.

BUG=chromium:579905
R=adamk
LOG=Y

Committed: https://crrev.com/03ce7711e474a0ef74f723b30ae1527c89dec010
Cr-Commit-Position: refs/heads/master@{#33501}
==========

[commit-bot: I haz the power, 2016-01-25 20:26:55]

Patchset 2 (id:??) landed as
https://crrev.com/03ce7711e474a0ef74f723b30ae1527c89dec010
Cr-Commit-Position: refs/heads/master@{#33501}

[Dan Ehrenberg, 2016-03-18 18:03:47]

A revert of this CL (patchset #2 id:20001) has been created in
https://codereview.chromium.org/1812143004/ by littledan@chromium.org.

The reason for reverting is: This patch actually seemed to cause a further
GameBoy regression! Reverting it seems to address the regression.

BUG=chromium:593634.