Backed out changeset 23eebebb8b48 (from bug 322475, which made us construct all our image loaders at frame construction time) because of issues with propagation of backgrounds to the canvas (bug 460796).

layout/generic/nsHTMLReflowState.cpp

@@ -289,6 +289,17 @@ nsHTMLReflowState::Init(nsPresContext* aPresContext,
 
   InitResizeFlags(aPresContext);
 
+  // We have to start loading the border image now, because the
+  // border-image's width overrides only apply once the image is loaded.
+  // Starting the load of the image means we'll get a reflow when the
+  // image loads.  (If we didn't do it now, and the image loaded between
+  // reflow and paint, we'd never get the notification, and our size
+  // would be wrong.)
+  imgIRequest *borderImage = mStyleBorder->GetBorderImage();
+  if (borderImage) {
+    aPresContext->LoadBorderImage(borderImage, frame);
+  }
+
   NS_ASSERTION((mFrameType == NS_CSS_FRAME_TYPE_INLINE &&
                 !frame->IsFrameOfType(nsIFrame::eReplaced)) ||
                frame->GetType() == nsGkAtoms::textFrame ||