[FIX] web: prevent crash in ungrouped kanban views with progressbar

The progressbar widget is not supposed to be displayed in non grouped
mode.  Before this commit, this situation resulted in a traceback. For
example, if the user has an activity on the subscription model, and
tries to open it, it will open an ungrouped kanban view.

With this commit, we check first that the kanban view is in grouped
mode, before loading the progress bar data.

addons/web/static/src/js/views/kanban/kanban_model.js

@@ -305,7 +305,7 @@ var KanbanModel = BasicModel.extend({
      * @override
      */
     _load: function (dataPoint, options) {
-        if (dataPoint.progressBar) {
+        if (dataPoint.groupedBy.length && dataPoint.progressBar) {
             return this._readProgressBarGroup(dataPoint, options);
         }
         return this._super.apply(this, arguments);

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

@@ -4232,6 +4232,37 @@ QUnit.module('Views', {
         kanban.destroy();
     });
 
+    QUnit.test('column progressbars should not crash in non grouped views', function (assert) {
+        assert.expect(3);
+
+        var kanban = createView({
+            View: KanbanView,
+            model: 'partner',
+            data: this.data,
+            arch:
+                '<kanban>' +
+                    '<field name="bar"/>' +
+                    '<field name="int_field"/>' +
+                    '<progressbar field="foo" colors=\'{"yop": "success", "gnap": "warning", "blip": "danger"}\' sum_field="int_field"/>' +
+                    '<templates><t t-name="kanban-box">' +
+                        '<div>' +
+                            '<field name="name"/>' +
+                        '</div>' +
+                    '</t></templates>' +
+                '</kanban>',
+            mockRPC: function (route, args) {
+                assert.step(route)
+                return this._super(route, args);
+            },
+        });
+
+        assert.strictEqual(kanban.$('.o_kanban_record').text(), 'namenamenamename',
+            "should have renderer 4 records");
+
+        assert.verifySteps(['/web/dataset/search_read'], "no read on progress bar data is done");
+        kanban.destroy();
+    });
+
     QUnit.test('column progressbars: creating a new column should create a new progressbar', function (assert) {
         assert.expect(1);