Make loading screen come much earlier on pad2

www/common/loading.js

@@ -1,5 +1,5 @@
 define([
-    'less!/customize/src/less/cryptpad.less'
+    'less!/customize/src/less/loading.less'
 ], function () {
     var urlArgs = window.location.href.replace(/^.*\?([^\?]*)$/, function (all, x) { return x; });
     var elem = document.createElement('div');

www/common/sframe-boot.js

@@ -9,11 +9,22 @@ if (req.pfx) {
     };
 }
 require.config(req.cfg);
-if (req.req) { require(req.req, function () { }); }
-window.addEventListener('message', function (msg) {
+var txid = Math.random().toString(16).replace('0.', '');
+var intr;
+var ready = function () {
+    intr = setInterval(function () {
+        if (typeof(txid) !== 'string') { return; }
+        window.parent.postMessage(JSON.stringify({ q: 'READY', txid: txid }), '*');
+    }, 1);
+};
+if (req.req) { require(req.req, ready); } else { ready(); }
+var onReply = function (msg) {
     var data = JSON.parse(msg.data);
-    if (data.q !== 'INIT') { return; }
-    msg.source.postMessage(JSON.stringify({ txid: data.txid, content: 'OK' }), '*');
+    if (data.txid !== txid) { return; }
+    clearInterval(intr);
+    txid = {};
+    window.removeEventListener('message', onReply);
     require(['/common/sframe-boot2.js'], function () { });
-});
+};
+window.addEventListener('message', onReply);
 }());

www/common/sframe-channel.js

@@ -105,7 +105,6 @@ define([
             insideHandlers.push(content);
         }, true);
 
-        var intr;
         var txid;
         window.addEventListener('message', function (msg) {
             var data = JSON.parse(msg.data);
@@ -113,12 +112,8 @@ define([
                 console.log("DROP Message from unexpected source");
                 console.log(msg);
             } else if (!otherWindow) {
-                if (data.txid !== txid) {
-                    console.log("DROP Message with weird txid");
-                    return;
-                }
-                clearInterval(intr);
                 otherWindow = ow;
+                ow.postMessage(JSON.stringify({ txid: data.txid }), '*');
                 cb(chan);
             } else if (typeof(data.q) === 'string' && handlers[data.q]) {
                 handlers[data.q].forEach(function (f) {
@@ -139,17 +134,6 @@ define([
             // we're in the sandbox
             otherWindow = ow;
             cb(chan);
-        } else {
-            require(['/common/requireconfig.js'], function (RequireConfig) {
-                txid = mkTxid();
-                intr = setInterval(function () {
-                    ow.postMessage(JSON.stringify({
-                        txid: txid,
-                        content: { requireConf: RequireConfig() },
-                        q: 'INIT'
-                    }), '*');
-                }, 1);
-            });
         }
     };