[FIX] web: config.debug and session.debug equivalence

Before this rev., config.debug was always a boolean, whereas it
should also encode the special value 'assets', as done in session.

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

@@ -3,6 +3,7 @@ odoo.define('web.Session', function (require) {
 
 var ajax = require('web.ajax');
 var concurrency = require('web.concurrency');
+var config = require('web.config');
 var core = require('web.core');
 var mixins = require('web.mixins');
 var utils = require('web.utils');
@@ -37,8 +38,7 @@ var Session = core.Class.extend(mixins.EventDispatcherMixin, {
         this.avoid_recursion = false;
         this.use_cors = options.use_cors || false;
         this.setup(origin);
-        var debug_param = $.deparam($.param.querystring()).debug;
-        this.debug = (debug_param !== undefined ? debug_param || 1 : false);
+        this.debug = config.debug;
 
         // for historic reasons, the session requires a name to properly work
         // (see the methods get_cookie and set_cookie).  We should perhaps

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

@@ -10,14 +10,19 @@ odoo.define('web.config', function (require) {
  * this file someday.
  */
 
+var debugParam = $.deparam($.param.querystring()).debug;
+var debug = false;
+if (debugParam !== undefined) {
+    debug = debugParam === 'assets' ? 'assets' : true;
+}
+
 var config = {
     /**
-     * debug is a boolean flag.  It is only considered true if the flag is set
-     * in the url
+     * debug can be either a boolean, or the special value 'assets'
      *
-     * @type Boolean
+     * @type boolean|string
      */
-    debug: ($.deparam($.param.querystring()).debug !== undefined),
+    debug: debug,
     device: {
         /**
          * touch is a boolean, true if the device supports touch interaction