[FIX] web_advanced_search: Implement 'Add Custom Filter' for owl widgets (pivot, graph)

Steps to reproduce:

1. Go to any Pivot or Graph view.
2. Add a custom filter, for example, Company.
3. Use the "is equal to" operator.

Result:

Uncaught Promise > Cannot find the definition of component "RecordPicker"

---

This happens because in Odoo 15.0 there are two versions of the FilterMenu and
CustomFilterItem widgets: one implemented in the legacy widget framework [^1]
and another implemented in Owl [^2].

The legacy version is used for `tree` views, for example; whilst the Owl version
is used for `pivot` and `graph` views.

Confusing as it is, before this commit only the legacy version was being overriden,
making it work for `tree` views (most common case), but not for `pivot` views.

Since both versions share the same QWeb template, though, not only it wasn't
working for `pivot`, but it also raised an Exception.

[^1]: https://github.com/odoo/odoo/blob/21a2dfd90/addons/web/static/src/legacy/js/control_panel/custom_filter_item.js#L45
[^2]: https://github.com/odoo/odoo/blob/21a2dfd90/addons/web/static/src/search/filter_menu/custom_filter_item.js#L107

web_advanced_search/static/src/js/RecordPicker.esm.js

@@ -105,6 +105,9 @@ export const FakeMany2oneFieldWidget = FieldMany2One.extend(FieldManagerMixin, {
 });
 
 export class FakeMany2oneFieldWidgetAdapter extends ComponentAdapter {
+    setup() {
+        this.env = owl.Component.env;
+    }
     async updateWidget() {
         /* eslint-disable no-empty-function */
     }

web_advanced_search/static/src/js/legacy/CustomFilterItem.esm.js

@@ -4,7 +4,12 @@ import {patch} from "@web/core/utils/patch";
 import CustomFilterItem from "web.CustomFilterItem";
 import {RecordPicker} from "../RecordPicker.esm";
 
-
+/**
+ * Patches the CustomFilterItem for legacy widgets.
+ *
+ * Tree views still use this old legacy widget, so we need to patch it.
+ * This is likely to dissapear in 16.0
+ */
 patch(CustomFilterItem.prototype, "web_advanced_search.legacy.CustomFilterItem", {
     /**
      * Ideally we'd want this in setup, but CustomFilterItem does its initialization

web_advanced_search/static/src/js/legacy/FilterMenu.esm.js

@@ -4,7 +4,12 @@ import {patch} from "@web/core/utils/patch";
 import FilterMenu from "web.FilterMenu";
 import AdvancedFilterItem from "../AdvancedFilterItem.esm";
 
-
+/**
+ * Patches the FilterMenu for legacy widgets.
+ *
+ * Tree views still use this old legacy widget, so we need to patch it.
+ * This is likely to dissapear in 16.0
+ */
 patch(FilterMenu, "web_advanced_search.legacy.FilterMenu", {
     components: {
         ...FilterMenu.components,

web_advanced_search/static/src/js/owl/CustomFilterItem.esm.js

@@ -0,0 +1,87 @@
+/** @odoo-module **/
+
+import {patch} from "@web/core/utils/patch";
+import {CustomFilterItem} from "@web/search/filter_menu/custom_filter_item";
+import {RecordPicker} from "../RecordPicker.esm";
+
+/**
+ * Patches the CustomFilterItem for owl widgets.
+ *
+ * Pivot and Graph views use this new owl widget, so we need to patch it.
+ * Other views like Tree use the old legacy widget that will probably dissapear
+ * in 16.0. Until then, we need to patch both.
+ */
+patch(CustomFilterItem.prototype, "web_advanced_search.CustomFilterItem", {
+    /**
+     * @override
+     */
+    setup() {
+        this._super.apply(this, arguments);
+        this.OPERATORS.relational = this.OPERATORS.char;
+        this.FIELD_TYPES.many2one = "relational";
+    },
+    /**
+     * @override
+     */
+    setDefaultValue(condition) {
+        const res = this._super.apply(this, arguments);
+        const fieldType = this.fields[condition.field].type;
+        const genericType = this.FIELD_TYPES[fieldType];
+        if (genericType === "relational") {
+            condition.value = 0;
+            condition.displayedValue = "";
+        }
+        return res;
+    },
+    /**
+     * Add displayed value to preFilters for "relational" types.
+     *
+     * @override
+     */
+    onApply() {
+        // To avoid the complete override, we patch this.conditions.map()
+        const originalMapFn = this.conditions.map;
+        const self = this;
+        this.conditions.map = function () {
+            const preFilters = originalMapFn.apply(this, arguments);
+            for (const condition of this) {
+                const field = self.fields[condition.field];
+                const type = self.FIELD_TYPES[field.type];
+                if (type === "relational") {
+                    const idx = this.indexOf(condition);
+                    const preFilter = preFilters[idx];
+                    const operator = self.OPERATORS[type][condition.operator];
+                    const descriptionArray = [
+                        field.string,
+                        operator.description,
+                        `"${condition.displayedValue}"`,
+                    ];
+                    preFilter.description = descriptionArray.join(" ");
+                }
+            }
+            return preFilters;
+        };
+        const res = this._super.apply(this, arguments);
+        // Restore original map()
+        this.conditions.map = originalMapFn;
+        return res;
+    },
+    /**
+     * @private
+     * @param {Object} condition
+     * @param {OwlEvent} ev
+     */
+    onRelationalChanged(condition, ev) {
+        condition.value = ev.detail.id;
+        condition.displayedValue = ev.detail.display_name;
+    },
+});
+
+patch(CustomFilterItem, "web_advanced_search.CustomFilterItem", {
+    components: {
+        ...CustomFilterItem.components,
+        RecordPicker,
+    },
+});
+
+export default CustomFilterItem;

web_advanced_search/static/src/js/owl/FilterMenu.esm.js

@@ -0,0 +1,21 @@
+/** @odoo-module **/
+
+import {patch} from "@web/core/utils/patch";
+import {FilterMenu} from "@web/search/filter_menu/filter_menu";
+import AdvancedFilterItem from "../AdvancedFilterItem.esm";
+
+/**
+ * Patches the FilterMenu for owl widgets.
+ *
+ * Pivot and Graph views use this new owl widget, so we need to patch it.
+ * Other views like Tree use the old legacy widget that will probably dissapear
+ * in 16.0. Until then, we need to patch both.
+ */
+patch(FilterMenu, "web_advanced_search.FilterMenu", {
+    components: {
+        ...FilterMenu.components,
+        AdvancedFilterItem,
+    },
+});
+
+export default FilterMenu;