b=657041 initialize with NS_MATHML_STRETCH_ALL_CHILDREN_VERTICALLY for when InheritAutomaticData does not get called r=fred

--HG--
extra : transplant_source : %E3%07S3%ABv%EC%B67%5C%25%29CH%12%99%8C%B43P

layout/mathml/crashtests/crashtests.list

@@ -32,7 +32,7 @@ load 375562-1.xhtml
 load 377824-1.xhtml
 load 379418-1.xhtml
 load 385226-1.xhtml
-asserts(2-3) load 393760-1.xhtml # Bug 541620
+load 393760-1.xhtml
 load 397518-1.xhtml
 load 400475-1.xhtml
 load 402400-1.xhtml

layout/mathml/nsMathMLmfencedFrame.cpp

@@ -88,6 +88,10 @@ nsMathMLmfencedFrame::SetInitialChildList(nsIAtom*        aListName,
   nsresult rv = nsMathMLContainerFrame::SetInitialChildList(aListName, aChildList);
   if (NS_FAILED(rv)) return rv;
 
+  // InheritAutomaticData will not get called if our parent is not a mathml
+  // frame, so initialize NS_MATHML_STRETCH_ALL_CHILDREN_VERTICALLY for
+  // GetPreferredStretchSize() from Reflow().
+  mPresentationData.flags |= NS_MATHML_STRETCH_ALL_CHILDREN_VERTICALLY;
   // No need to track the style contexts given to our MathML chars. 
   // The Style System will use Get/SetAdditionalStyleContext() to keep them
   // up-to-date if dynamic changes arise.
@@ -310,8 +314,6 @@ nsMathMLmfencedFrame::Reflow(nsPresContext*          aPresContext,
   nsBoundingMetrics containerSize;
   nsStretchDirection stretchDir = NS_STRETCH_DIRECTION_VERTICAL;
 
-  nsPresentationData presentationData;
-  GetPresentationData(presentationData);
   GetPreferredStretchSize(*aReflowState.rendContext,
                           0, /* i.e., without embellishments */
                           stretchDir, containerSize);