[FIX] web: groups of filters ordered correctly

In the filters menus, the order of groups of filters comming
from the search view arch was not always preserved in the filters menu.
This commit fixes that situation.

forward-port of @4094f755

addons/web/static/src/js/views/search/groupby_menu_interface_mixin.js

@@ -54,6 +54,7 @@ var GroupByMenuInterfaceMixin = {
                 defaultOptionId: groupby ? groupby.interval : false,
             });
         });
+        groupbys = _.sortBy(groupbys, 'description');
         var groupByMenu = new GroupByMenu(this, groupbys, groupableFields, {headerStyle: 'primary'});
         groupByMenu.insertAfter($node.find('div:first'));
     },

addons/web/static/src/js/widgets/dropdown_menu.js

@@ -52,7 +52,7 @@ var DropdownMenu = Widget.extend({
                 el: {class: 'btn-group o_dropdown', attrs: {}},
                 mainButton: {class: 'o_dropdown_toggler_btn btn btn-sm btn-default dropdown-toggle'},
             };
-        this.items = _.sortBy(items, 'groupId');
+        this.items = items;
         _.each(this.items, this._prepareItem.bind(this));
     },
     /**

addons/web/static/tests/views/search_view_tests.js

@@ -78,11 +78,18 @@ QUnit.module('Search View', {
             search_view_id: [5, 'search'],
         }, {
             id: 7,
-            name: 'Partners Action 8',
+            name: 'Partners Action 7',
             res_model: 'partner',
             type: 'ir.actions.act_window',
             views: [[2, 'list']],
             search_view_id: [6, 'search'],
+        }, {
+            id: 8,
+            name: 'Partners Action 8',
+            res_model: 'partner',
+            type: 'ir.actions.act_window',
+            views: [[2, 'list']],
+            search_view_id: [7, 'search'],
         }
         ];
 
@@ -118,12 +125,35 @@ QUnit.module('Search View', {
             'partner,5,search': '<search>'+
                     '<filter string="Date Field Filter" name="positive" date="date_field"/>' +
                     '<filter string="Date Field Groupby" name="coolName" context="{\'group_by\': \'date_field:day\'}"/>' +
-            '</search>',
+                '</search>',
             'partner,6,search': '<search>'+
                     '<filter string="Date" name="coolName" context="{\'group_by\': \'date_field:day\'}"/>' +
                     '<separator/>' +
                     '<filter string="Bar" name="superName" context="{\'group_by\': \'bar\'}"/>' +
-            '</search>',
+                '</search>',
+            'partner,7,search': '<search>'+
+                    '<filter string="1" name="coolName1" date="date_field"/>' +
+                    '<separator/>' +
+                    '<filter string="2" name="coolName2" date="birthday"/>' +
+                    '<separator/>' +
+                    '<filter string="3" name="coolName3" domain="[]"/>' +
+                    '<separator/>' +
+                    '<filter string="4" name="coolName4" domain="[]"/>' +
+                    '<separator/>' +
+                    '<filter string="5" name="coolName5" domain="[]"/>' +
+                    '<separator/>' +
+                    '<filter string="6" name="coolName6" domain="[]"/>' +
+                    '<separator/>' +
+                    '<filter string="7" name="coolName7" domain="[]"/>' +
+                    '<separator/>' +
+                    '<filter string="8" name="coolName8" domain="[]"/>' +
+                    '<separator/>' +
+                    '<filter string="9" name="coolName9" domain="[]"/>' +
+                    '<separator/>' +
+                    '<filter string="10" name="coolName10" domain="[]"/>' +
+                    '<separator/>' +
+                    '<filter string="11" name="coolName11" domain="[]"/>' +
+                '</search>',
         };
     },
 }, function () {
@@ -475,5 +505,23 @@ QUnit.module('Search View', {
         $('.o_favorites_menu .o_save_name button').click();
         actionManager.destroy();
     });
+
+    QUnit.test('arch order of groups of filters preserved', function (assert) {
+        assert.expect(12);
+
+        var actionManager = createActionManager({
+            actions: this.actions,
+            archs: this.archs,
+            data: this.data,
+        });
+
+        actionManager.doAction(8);
+        $('span.fa-filter').click();
+        assert.strictEqual($('.o_filters_menu .o_menu_item').length, 11);
+        for (var i = 0;  i < 11; i++) {
+            assert.strictEqual($('.o_filters_menu .o_menu_item').eq(i).text().trim(), (i+1).toString());
+        }
+        actionManager.destroy();
+    });
 });
 });