[FIX] web: Graph: correctly return graph's context

allowing to properly save the current state (mode, measure,
groupbys) of the view in the Favorites or add it to the dashboard.

addons/web/static/src/js/views/graph/graph_controller.js

@@ -39,6 +39,22 @@ var GraphController = AbstractController.extend({
     // Public
     //--------------------------------------------------------------------------
 
+    /**
+     * Returns the current mode, measure and groupbys, so we can restore the
+     * view when we save the current state in the search view, or when we add it
+     * to the dashboard.
+     *
+     * @override
+     * @returns {Object}
+     */
+    getContext: function () {
+        var state = this.model.get();
+        return {
+            graph_measure: state.measure,
+            graph_mode: state.mode,
+            graph_groupbys: state.groupedBy,
+        };
+    },
     /**
      * Render the buttons according to the GraphView.buttons and
      * add listeners on it.

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

@@ -251,6 +251,59 @@ QUnit.module('Views', {
         });
     });
 
+    QUnit.test('getContext correctly returns mode, measure and groupbys', function (assert) {
+        var done = assert.async();
+        assert.expect(4);
+
+        var graph = createView({
+            View: GraphView,
+            model: "foo",
+            data: this.data,
+            arch: '<graph string="Gloups">' +
+                        '<field name="product_id"/>' +
+                '</graph>',
+        });
+        return concurrency.delay(0).then(function () {
+            assert.deepEqual(graph.getContext(), {
+                graph_mode: 'bar',
+                graph_measure: '__count__',
+                graph_groupbys: ['product_id'],
+            }, "context should be correct");
+
+            graph.$buttons.find('li[data-field="foo"] a').click(); // change measure
+
+            return concurrency.delay(0);
+        }).then(function () {
+            assert.deepEqual(graph.getContext(), {
+                graph_mode: 'bar',
+                graph_measure: 'foo',
+                graph_groupbys: ['product_id'],
+            }, "context should be correct");
+
+            graph.$buttons.find('button[data-mode="line"]').click(); // change mode
+
+            return concurrency.delay(0);
+        }).then(function () {
+            assert.deepEqual(graph.getContext(), {
+                graph_mode: 'line',
+                graph_measure: 'foo',
+                graph_groupbys: ['product_id'],
+            }, "context should be correct");
+
+            graph.update({groupBy: ['product_id', 'color_id']}); // change groupbys
+
+            return concurrency.delay(0);
+        }).then(function () {
+            assert.deepEqual(graph.getContext(), {
+                graph_mode: 'line',
+                graph_measure: 'foo',
+                graph_groupbys: ['product_id', 'color_id'],
+            }, "context should be correct");
+
+            graph.destroy();
+            done();
+        });
+    });
 });
 
 });