Bug 26100: Use new asynchronous applyFilter

applyFilter changed its signature to include a callback
object:
https://hg.mozilla.org/mozilla-central/rev/77c14093bc69

src/components/domain-isolator.js

@@ -43,8 +43,8 @@ mozilla.protocolProxyService = Cc["@mozilla.org/network/protocol-proxy-service;1
 // for the given channel, and should return a new Proxy or list of Proxies.
 mozilla.registerProxyChannelFilter = function (filterFunction, positionIndex) {
   let proxyFilter = {
-    applyFilter : function (aProxyService, aChannel, aProxy) {
-      return filterFunction(aChannel, aProxy);
+    applyFilter : function (aProxyService, aChannel, aProxy, aCallback) {
+      aCallback.onProxyFilterResult(filterFunction(aChannel, aProxy));
     }
   };
   mozilla.protocolProxyService.registerChannelFilter(proxyFilter, positionIndex);