Report size of the external memory to V8 in StaticNodeList

Report size of the external memory to V8 in StaticNodeList

When we create a lot of moderately large NodeLists, the V8 GC heuristic
isn't aggressively enough collecting wrappers which can lead to an OOM
crash. Reporting the size of the nodelists to V8 fixes this issue.

The other kinds of nodelists don't have variable sized members, so they
don't have this problem

BUG=315082
TEST=opening PerformanceTests/Parser/query-selector-all-class.html in a release build content shell on a fast computer doesn't crash.
R=dslomov@chromium.org

Committed: https://src.chromium.org/viewvc/blink?view=rev&revision=161546

[jochen (gone - plz use gerrit), 2013-11-07 13:15:55]

plz review

[Dmitry Lomov (no reviews), 2013-11-07 14:29:46]

On 2013/11/07 13:15:55, jochen wrote:
> plz review

Hmm, you adjust V8 external memory even for NodeLists that are never exposed to
V8 - is that ok?

[jochen (gone - plz use gerrit), 2013-11-07 14:35:53]

On 2013/11/07 14:29:46, Dmitry Lomov (chromium) wrote:
> On 2013/11/07 13:15:55, jochen wrote:
> > plz review
> 
> Hmm, you adjust V8 external memory even for NodeLists that are never exposed
to
> V8 - is that ok?

You tell me :)

The other places in Source/core that adjust the memory are also doing this
unconditionally.

Also, unless you go full custom as you did with Array buffers, there's no notion
of being script exposed or not

[Dmitry Lomov (no reviews), 2013-11-07 15:13:39]

On 2013/11/07 14:35:53, jochen wrote:
> On 2013/11/07 14:29:46, Dmitry Lomov (chromium) wrote:
> > On 2013/11/07 13:15:55, jochen wrote:
> > > plz review
> > 
> > Hmm, you adjust V8 external memory even for NodeLists that are never exposed
> to
> > V8 - is that ok?
> 
> You tell me :)
> 
> The other places in Source/core that adjust the memory are also doing this
> unconditionally.
> 
> Also, unless you go full custom as you did with Array buffers, there's no
notion
> of being script exposed or not

Hmm ok, LGTM then I guess.
I guess the reason why we get away with inaccurate reporting here is because the
objects are small and statistically most of them are exposed to V8 anyway.
ArrayBuffers are large, and not all of them are exposed to V8. Let's see what
happens here.

[haraken, 2013-11-07 15:25:01]

LGTM. The AdjustAmountOfMemory calls in this CL are balanced, so it looks
definitely safe.

[commit-bot: I haz the power, 2013-11-07 15:25:56]

CQ is trying da patch. Follow status at
https://chromium-status.appspot.com/cq/jochen@chromium.org/64203002/90001

[commit-bot: I haz the power, 2013-11-07 17:43:11]

Change committed as 161546