ValueSerializer: Check for zero length before casting to FixedDoubleArray.

ValueSerializer: Check for zero length before casting to FixedDoubleArray.

Even though the elements kind is FAST_DOUBLE_ELEMENTS, if length is zero
the isolate's empty_fixed_array is used. It's illegal to cast this to
FixedDoubleArray, so we avoid the cast.

BUG=chromium:686479
Review-Url: https://codereview.chromium.org/2665313003
Cr-Commit-Position: refs/heads/master@{#42867}
Committed: https://chromium.googlesource.com/v8/v8/+/c3856de3714e62943d4bed100346158c227318a4

[jbroman, 2017-02-01 05:22:54]

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

[commit-bot: I haz the power, 2017-02-01 05:22:56]

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, 2017-02-01 05:56:02]

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

[commit-bot: I haz the power, 2017-02-01 05:56:03]

Dry run: This issue passed the CQ dry run.

[jbroman, 2017-02-01 06:07:57]

jbroman@chromium.org changed reviewers:
+ binji@chromium.org

[binji, 2017-02-01 20:13:08]

lgtm

[jbroman, 2017-02-01 20:22:33]

The CQ bit was checked by jbroman@chromium.org

[commit-bot: I haz the power, 2017-02-01 20:22:44]

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, 2017-02-01 20:25:57]

CQ is committing da patch.

Bot data: {"patchset_id": 1, "attempt_start_ts": 1485980553021750, "parent_rev":
"4975ac41c3fcad49fcfaf36b88ac081b692b8555", "commit_rev":
"c3856de3714e62943d4bed100346158c227318a4"}

[commit-bot: I haz the power, 2017-02-01 20:26:01]

Description was changed from

==========
ValueSerializer: Check for zero length before casting to FixedDoubleArray.

Even though the elements kind is FAST_DOUBLE_ELEMENTS, if length is zero
the isolate's empty_fixed_array is used. It's illegal to cast this to
FixedDoubleArray, so we avoid the cast.

BUG=chromium:686479
==========

to

==========
ValueSerializer: Check for zero length before casting to FixedDoubleArray.

Even though the elements kind is FAST_DOUBLE_ELEMENTS, if length is zero
the isolate's empty_fixed_array is used. It's illegal to cast this to
FixedDoubleArray, so we avoid the cast.

BUG=chromium:686479

Review-Url: https://codereview.chromium.org/2665313003
Cr-Commit-Position: refs/heads/master@{#42867}
Committed:
https://chromium.googlesource.com/v8/v8/+/c3856de3714e62943d4bed100346158c227...
==========

[commit-bot: I haz the power, 2017-02-01 20:26:03]

Committed patchset #1 (id:1) as
https://chromium.googlesource.com/v8/v8/+/c3856de3714e62943d4bed100346158c227...