Fallback to jsonp-polling in IE when going cross scheme.

sockjs/sockjs-client#79

packages/stream/sockjs-0.3.1.js

@@ -1,3 +1,5 @@
+// XXX METEOR changes in <METEOR>
+
 /* SockJS client, version 0.3.1, http://sockjs.org, MIT License
 
 Copyright (c) 2011-2012 VMware, Inc.
@@ -202,6 +204,17 @@ utils.isSameOriginUrl = function(url_a, url_b) {
             url_b.split('/').slice(0,3).join('/'));
 };
 
+// <METEOR>
+utils.isSameOriginScheme = function(url_a, url_b) {
+    if (!url_b) url_b = _window.location.href;
+
+    return (url_a.split(':')[0]
+                ===
+            url_b.split(':')[0]);
+};
+// </METEOR>
+
+
 utils.getParentDomain = function(url) {
     // ipv4 ip address
     if (/^[0-9.]*$/.test(url)) return url;
@@ -1148,6 +1161,14 @@ SockJS.prototype._applyInfo = function(info, rtt, protocols_whitelist) {
     that._options.info.null_origin = !_document.domain;
     var probed = utils.probeProtocols();
     that._protocols = utils.detectProtocols(probed, protocols_whitelist, info);
+// <METEOR>
+    // Hack to avoid XDR when using different protocols
+    // We're on IE trying to do cross-protocol. jsonp only.
+    if (!utils.isSameOriginScheme(that._base_url) &&
+        2 === utils.isXHRCorsCapable()) {
+        that._protocols = ['jsonp-polling'];
+    }
+// </METEOR>
 };
 //         [*] End of lib/sockjs.js
 
@@ -1945,7 +1966,14 @@ var createInfoReceiver = function(base_url) {
     case 1:
         return new InfoReceiver(base_url, utils.XHRCorsObject);
     case 2:
-        return new InfoReceiver(base_url, utils.XDRObject);
+// <METEOR>
+        // XDR doesn't work across different schemes
+        // http://blogs.msdn.com/b/ieinternals/archive/2010/05/13/xdomainrequest-restrictions-limitations-and-workarounds.aspx
+        if (utils.isSameOriginScheme(base_url))
+            return new InfoReceiver(base_url, utils.XDRObject);
+        else
+            return new InfoReceiverFake();
+// </METEOR>
     case 3:
         // Opera
         return new InfoReceiverIframe(base_url);