ScrollingStateTree::rootStateNode() should be null-checked since it can be null
authorbdakin@apple.com <bdakin@apple.com@268f45cc-cd09-0410-ab3c-d52691b4dbfc>
Fri, 22 Feb 2013 21:38:08 +0000 (21:38 +0000)
committerbdakin@apple.com <bdakin@apple.com@268f45cc-cd09-0410-ab3c-d52691b4dbfc>
Fri, 22 Feb 2013 21:38:08 +0000 (21:38 +0000)
commit6853d128d5d4fc541bc0f9fc58cc9a73fc1c4246
tree67ca66d9c44b363458a7fdc58ada015ea38f8037
parente014c9aca2834bf79d611a6214304e818c8de886
ScrollingStateTree::rootStateNode() should be null-checked since it can be null
https://bugs.webkit.org/show_bug.cgi?id=110631

Reviewed by Simon Fraser.

This is a speculative fix for <rdar://problem/13233090> and
<rdar://problem/12519348>. It is totally possible for rootStateNode() to be null,
so we should null-check it.

* page/scrolling/mac/ScrollingCoordinatorMac.mm:
(WebCore::ScrollingCoordinatorMac::setShouldUpdateScrollLayerPositionOnMainThread):
(WebCore::ScrollingCoordinatorMac::syncChildPositions):

git-svn-id: https://svn.webkit.org/repository/webkit/trunk@143785 268f45cc-cd09-0410-ab3c-d52691b4dbfc
Source/WebCore/ChangeLog
Source/WebCore/page/scrolling/mac/ScrollingCoordinatorMac.mm