Bug 302566. Show canvas fallback content when script is disabled. r=tnikkel

layout/base/nsCSSFrameConstructor.cpp

@@ -3527,7 +3527,7 @@ nsCSSFrameConstructor::FindHTMLData(Element* aElement,
     SIMPLE_TAG_CREATE(frameset, NS_NewHTMLFramesetFrame),
     SIMPLE_TAG_CREATE(iframe, NS_NewSubDocumentFrame),
     COMPLEX_TAG_CREATE(button, &nsCSSFrameConstructor::ConstructButtonFrame),
-    SIMPLE_TAG_CREATE(canvas, NS_NewHTMLCanvasFrame),
+    SIMPLE_TAG_CHAIN(canvas, nsCSSFrameConstructor::FindCanvasData),
 #if defined(MOZ_MEDIA)
     SIMPLE_TAG_CREATE(video, NS_NewHTMLVideoFrame),
     SIMPLE_TAG_CREATE(audio, NS_NewHTMLVideoFrame),
@@ -3638,6 +3638,20 @@ nsCSSFrameConstructor::FindObjectData(Element* aElement,
                        sObjectData, ArrayLength(sObjectData));
 }
 
+/* static */
+const nsCSSFrameConstructor::FrameConstructionData*
+nsCSSFrameConstructor::FindCanvasData(Element* aElement,
+                                      nsStyleContext* aStyleContext)
+{
+  if (!aElement->OwnerDoc()->IsScriptEnabled()) {
+    return nsnull;
+  }
+
+  static const FrameConstructionData sCanvasData =
+    SIMPLE_FCDATA(NS_NewHTMLCanvasFrame);
+  return &sCanvasData;
+}
+
 nsresult
 nsCSSFrameConstructor::ConstructFrameFromItemInternal(FrameConstructionItem& aItem,
                                                       nsFrameConstructorState& aState,

layout/base/nsCSSFrameConstructor.h

@@ -1201,6 +1201,8 @@ private:
     FindInputData(Element* aElement, nsStyleContext* aStyleContext);
   static const FrameConstructionData*
     FindObjectData(Element* aElement, nsStyleContext* aStyleContext);
+  static const FrameConstructionData*
+    FindCanvasData(Element* aElement, nsStyleContext* aStyleContext);
 
   /* Construct a frame from the given FrameConstructionItem.  This function
      will handle adding the frame to frame lists, processing children, setting