[FIX] web: prevent crash sometimes when sorting one2many

Before this commit, there was a crash when sorting a one2many in a form view.
This is due to the fact that the event from the one2many bubbled up to
the main form view, which basically assumed that it was supposed to sort
some sub one2many.

It could be seen for example when editing a 'attribute' in a product
form view (need to activate variants), then sorting the 'attribute
values' sub one2many.

With this commit, we simply stop the event propagation at the correct
level.

addons/web/static/src/js/views/form/form_controller.js

@@ -514,6 +514,7 @@ var FormController = BasicController.extend({
      * @param {OdooEvent} event
      */
     _onToggleColumnOrder: function (event) {
+        event.stopPropagation();
         this.model.setSort(event.data.id, event.data.name);
         var field = event.data.field;
         var state = this.model.get(this.handle);

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

@@ -5842,5 +5842,45 @@ QUnit.module('Views', {
             "there should be only one column");
         form.destroy();
     });
+
+    QUnit.test('can toggle column in x2many in sub form view', function (assert) {
+        assert.expect(2);
+
+        this.data.partner.records[2].p = [1,2];
+        this.data.partner.fields.foo.sortable = true;
+        var form = createView({
+            View: FormView,
+            model: 'partner',
+            data: this.data,
+            arch: '<form string="Partners">' +
+                    '<field name="trululu"/>' +
+                '</form>',
+            res_id: 1,
+            mockRPC: function (route, args) {
+                if (route === '/web/dataset/call_kw/partner/get_formview_id') {
+                    return $.when(false);
+                }
+                return this._super.apply(this, arguments);
+            },
+            archs: {
+                'partner,false,form': '<form string="Partners">' +
+                        '<field name="p">' +
+                            '<tree>' +
+                                '<field name="foo"/>' +
+                            '</tree>' +
+                        '</field>' +
+                    '</form>',
+            },
+            viewOptions: {mode: 'edit'},
+        });
+        form.$('.o_external_button').click();
+        assert.strictEqual($('.modal-body .o_form_view .o_list_view .o_data_cell').text(), "yopblip",
+            "table has some initial order");
+
+        $('.modal-body .o_form_view .o_list_view th').click();
+        assert.strictEqual($('.modal-body .o_form_view .o_list_view .o_data_cell').text(), "blipyop",
+            "table is now sorted");
+        form.destroy();
+    });
 });
 });