Add a code to unescape with a charset for a non ASCII file name,

bug 163682, r=jbetak, sr=bzbarsky, a=rjesup@wgate.com.

xpfe/communicator/resources/content/contentAreaUtils.js

@@ -651,10 +651,25 @@ function getDefaultFileName(aDefaultFileName, aNameFromHeaders, aDocumentURI, aD
       // 2) Use the actual file name, if present
       return unescape(url.fileName);
     }
+  } catch (e) {
+    try {
+      // the file name might be non ASCII
+      // try unescape again with a characterSet
+      var textToSubURI = Components.classes["@mozilla.org/intl/texttosuburi;1"]
+                                   .getService(Components.interfaces.nsITextToSubURI);
+      var charset;
+      if (aDocument)
+        charset = aDocument.characterSet;
+      else if (document.commandDispatcher.focusedWindow)
+        charset = document.commandDispatcher.focusedWindow.document.characterSet;
+      else
+        charset = window._content.document.characterSet;
+      return textToSubURI.unEscapeURIForUI(charset, url.fileName);
     } catch (e) {
       // This is something like a wyciwyg:, data:, and so forth
       // URI... no usable filename here.
     }
+  }
   
   if (aDocument) {
     var docTitle = validateFileName(aDocument.title).replace(/^\s+|\s+$/g, "");