Bug 351297 - textPath elements must have text element parents r=tor,sr=roc

layout/base/nsCSSFrameConstructor.cpp

@@ -7774,9 +7774,8 @@ nsCSSFrameConstructor::ConstructSVGFrame(nsFrameConstructorState& aState,
     newFrame = NS_NewSVGClipPathFrame(mPresShell, aContent, aStyleContext);
   }
   else if (aTag == nsSVGAtoms::textPath) {
-    nsISVGTextContentMetrics* metrics;
-    CallQueryInterface(aParentFrame, &metrics);
-    if (metrics) {
+    if (aParentFrame &&
+        aParentFrame->GetType() == nsLayoutAtoms::svgTextFrame) {
       newFrame = NS_NewSVGTextPathFrame(mPresShell, aContent, aParentFrame, aStyleContext);
     }
   }

layout/svg/base/src/nsSVGTextPathFrame.cpp

@@ -60,15 +60,13 @@ NS_NewSVGTextPathFrame(nsIPresShell* aPresShell, nsIContent* aContent,
                        nsIFrame* parentFrame, nsStyleContext* aContext)
 {
   NS_ASSERTION(parentFrame, "null parent");
-  nsISVGTextContentMetrics *metrics;
-  CallQueryInterface(parentFrame, &metrics);
-  if (!metrics) {
+  if (parentFrame->GetType() != nsLayoutAtoms::svgTextFrame) {
     NS_ERROR("trying to construct an SVGTextPathFrame for an invalid container");
     return nsnull;
   }
   
-  nsCOMPtr<nsIDOMSVGTextPathElement> tspan_elem = do_QueryInterface(aContent);
-  if (!tspan_elem) {
+  nsCOMPtr<nsIDOMSVGTextPathElement> tpath_elem = do_QueryInterface(aContent);
+  if (!tpath_elem) {
     NS_ERROR("Trying to construct an SVGTextPathFrame for a "
              "content element that doesn't support the right interfaces");
     return nsnull;