Bug 365570 - FeedWriter doesn't work with handlers with chrome:// URI (throws exception when downloading favicon). r=gavin.

browser/components/feeds/src/FeedWriter.js

@@ -715,7 +715,7 @@ FeedWriter.prototype = {
         // For privacy reasons we cannot set the image attribute directly
         // to the icon url, see Bug 358878
         var uri = makeURI(handlers[i].uri);
-        if (uri) 
+        if (uri && /^https?/.test(uri.scheme))
           new iconDataURIGenerator(uri.prePath + "/favicon.ico", menuItem)
       }
     }

browser/components/preferences/feeds.js

@@ -187,8 +187,9 @@ var gFeedsPane = {
       row.setAttribute("webhandlerurl", handlers[i].uri);
 
       var uri = ios.newURI(handlers[i].uri, null, null);
-      row.setAttribute("image", uri.prePath + "/favicon.ico");
-      
+      if (/^https?/.test(uri.scheme))
+        row.setAttribute("image", uri.prePath + "/favicon.ico");
+
       readersList.appendChild(row);
     }
   },