Fix bug 347348 - Removing text node from <mo> causes 'ASSERTION: null arg' and has no visual effect, r+sr=roc

git-svn-id: svn://10.0.0.236/trunk@206789 18797224-902f-48f8-a5cc-f745e15eee43

mozilla/layout/mathml/base/src/nsMathMLmoFrame.cpp

@@ -974,6 +974,13 @@ nsMathMLmoFrame::ReflowDirtyChild(nsIPresShell* aPresShell,
   return ReLayoutChildren(target);
 }
 
+nsresult
+nsMathMLmoFrame::ChildListChanged(PRInt32 aModType)
+{
+  ProcessTextData(GetPresContext());
+  return nsMathMLContainerFrame::ChildListChanged(aModType);
+}
+
 NS_IMETHODIMP
 nsMathMLmoFrame::AttributeChanged(PRInt32         aNameSpaceID,
                                   nsIAtom*        aAttribute,

mozilla/layout/mathml/base/src/nsMathMLmoFrame.h

@@ -84,6 +84,9 @@ public:
                    nsIAtom*        aAttribute,
                    PRInt32         aModType);
 
+  virtual nsresult
+  ChildListChanged(PRInt32 aModType);
+
   // This method is called by the parent frame to ask <mo> 
   // to stretch itself.
   NS_IMETHOD