Move traverseLiveNodeListForwardToOffset() to LiveNodeList class

Move traverseLiveNodeListForwardToOffset() to LiveNodeList class

Move traverseLiveNodeListForwardToOffset() to LiveNodeList class and rename to
traverseForwardToOffset() for consistency with
HTMLCollection::traverseForwardToOffset(). Also merge
traverseChildNodeListForwardToOffset() into
LiveNodeList::traverseForwardToOffset() as ChildNodeList is a LiveNodeList and
there is no reason to treat it differently from the other LiveNodeList
subclasses.

Finally, rename isNodeList(CollectionType) to
isLiveNodeListType(CollectionType) as it only applies to LiveNodeLists and not
other types of NodeLists (e.g. StaticNodeList). This check is always used before
casting to a LiveNodeList.

R=abarth, esprehn, eseidel

Committed: https://src.chromium.org/viewvc/blink?view=rev&revision=164468

[Inactive, 2014-01-03 16:08:23]

Post-holidays ping review? :)

[eseidel, 2014-01-03 17:43:24]

lgtm

[commit-bot: I haz the power, 2014-01-03 17:43:51]

CQ is trying da patch. Follow status at
https://chromium-status.appspot.com/cq/ch.dumez@samsung.com/120593002/90001

[commit-bot: I haz the power, 2014-01-03 18:14:39]

Retried try job too often on linux_blink for step(s) webkit_tests
http://build.chromium.org/p/tryserver.chromium/buildstatus?builder=linux_blin...

[commit-bot: I haz the power, 2014-01-03 20:31:40]

CQ is trying da patch. Follow status at
https://chromium-status.appspot.com/cq/ch.dumez@samsung.com/120593002/220001

[commit-bot: I haz the power, 2014-01-03 22:06:31]

Change committed as 164468