Changeset 143785 in webkit

Timestamp:

Feb 22, 2013, 1:38:08 PM (12 years ago)

Author:

Beth Dakin

Message:

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):

Location:

trunk/Source/WebCore

Files:

• ChangeLog (modified) (1 diff)
• page/scrolling/mac/ScrollingCoordinatorMac.mm (modified) (2 diffs)

trunk/Source/WebCore/ChangeLog

@@ +1 @@
+2013-02-22  Beth Dakin  <bdakin@apple.com>
+
+        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):
+
 2013-02-22  Mike Reed  <reed@google.com>
 

trunk/Source/WebCore/page/scrolling/mac/ScrollingCoordinatorMac.mm

@@ -315 +315 @@
 void ScrollingCoordinatorMac::setShouldUpdateScrollLayerPositionOnMainThread(MainThreadScrollingReasons reasons)
 {
+    if (!m_scrollingStateTree->rootStateNode())
+        return;
+
     // The FrameView's GraphicsLayer is likely to be out-of-synch with the PlatformLayer
     // at this point. So we'll update it before we switch back to main thread scrolling
@@ -341 +344 @@
 void ScrollingCoordinatorMac::syncChildPositions(const LayoutRect& viewportRect)
 {
+    if (!m_scrollingStateTree->rootStateNode())
+        return;
+
     Vector<OwnPtr<ScrollingStateNode> >* children = m_scrollingStateTree->rootStateNode()->children();
     if (!children)