PerformanceTests/Bindings/scroll-top.html should use another DOM attribute

PerformanceTests/Bindings/scroll-top.html should use another DOM attribute

scroll-top.html is intended to test performance of DOM attributes that return small integers.
Due to a recent change to Element.scrollTop, Element.scrollTop no longer returns small integers
(it returns a double value). So this CL updates the performance test so that it uses Node.nodeType.

BUG=371429
Committed: https://src.chromium.org/viewvc/blink?view=rev&revision=175021

[haraken, 2014-05-29 00:52:11]

PTAL

[eae, 2014-05-29 00:59:09]

Great, thank you.

LGTM

[haraken, 2014-05-29 01:00:46]

The CQ bit was checked by haraken@chromium.org

[commit-bot: I haz the power, 2014-05-29 01:01:15]

CQ is trying da patch. Follow status at
 https://chromium-status.appspot.com/cq/haraken@chromium.org/306783003/1

[commit-bot: I haz the power, 2014-05-29 02:18:39]

Change committed as 175021