Merge r174126 - Remove a multicolumn ASSERT and replace with a guard.

https://bugs.webkit.org/show_bug.cgi?id=137272

Reviewed by Alexey Proskuryakov.

* rendering/RenderMultiColumnFlowThread.cpp:
(WebCore::isValidColumnSpanner):
For now remove the assert that is tripping and replace it with a guard
until we can figure out why it's getting hit.

Canonical link: https://commits.webkit.org/154760.62@webkitgtk/2.6
git-svn-id: https://svn.webkit.org/repository/webkit/releases/WebKitGTK/webkit-2.6@174450 268f45cc-cd09-0410-ab3c-d52691b4dbfc

Source/WebCore/ChangeLog

@@ -1,3 +1,15 @@
+2014-09-30  David Hyatt  <hyatt@apple.com>
+
+        Remove a multicolumn ASSERT and replace with a guard.
+        https://bugs.webkit.org/show_bug.cgi?id=137272
+
+        Reviewed by Alexey Proskuryakov.
+
+        * rendering/RenderMultiColumnFlowThread.cpp:
+        (WebCore::isValidColumnSpanner):
+        For now remove the assert that is tripping and replace it with a guard
+        until we can figure out why it's getting hit.
+
 2014-08-01  Sergio Villar Senin  <svillar@igalia.com>
 
         Caret not shown at the end of line in overtype mode

Source/WebCore/rendering/RenderMultiColumnFlowThread.cpp

@@ -245,8 +245,12 @@ RenderObject* RenderMultiColumnFlowThread::resolveMovedChild(RenderObject* child
 static bool isValidColumnSpanner(RenderMultiColumnFlowThread* flowThread, RenderObject* descendant)
 {
     // We assume that we're inside the flow thread. This function is not to be called otherwise.
-    ASSERT(descendant->isDescendantOf(flowThread));
-
+    // ASSERT(descendant->isDescendantOf(flowThread));
+    // FIXME: Put this back in when we figure out why spanner-crash.html is triggering it.
+    // See https://bugs.webkit.org/show_bug.cgi?id=137273
+    if (!descendant->isDescendantOf(flowThread))
+        return false;
+
     // First make sure that the renderer itself has the right properties for becoming a spanner.
     RenderStyle& style = descendant->style();
     if (style.columnSpan() != ColumnSpanAll || !descendant->isBox() || descendant->isFloatingOrOutOfFlowPositioned())