[IMP] web: start session service as soon as possible

addons/web/static/src/js/abstract_web_client.js

@@ -49,7 +49,7 @@ var WebClient = Widget.extend({
         this.on("change:title_part", this, this._title_changed);
         this._title_changed();
 
-        return session.session_bind(this.origin)
+        return session.is_bound
             .then(function () {
                 self.bind_events();
                 return $.when(

addons/web/static/src/js/services/session.js

@@ -4,6 +4,9 @@ odoo.define('web.session', function (require) {
 var Session = require('web.Session');
 var modules = odoo._modules;
 
-return new Session(undefined, undefined, {modules: modules, use_cors: false});
+var session = new Session(undefined, undefined, {modules: modules, use_cors: false});
+session.is_bound = session.session_bind();
+
+return session;
 
 });