[FIX] web: hang when saving then discarding

When editing a record, if it cannot be saved (b.e. due to required
fields) and the user clicks on save, then on discard

Before this fix, the window did nothing (seems like it is unresponsive)

After this fix, the user is able to discard the form.

task-id: 1937142

closes odoo/odoo#30871

1 files changed, 11 insertions, 5 deletions

diff --git a/addons/web/static/src/js/views/basic/basic_controller.js b/addons/web/static/src/js/views/basic/basic_controller.js
index 01bbd9cd2fe..16204c83163 100644
--- a/addons/web/static/src/js/views/basic/basic_controller.js
+++ b/addons/web/static/src/js/views/basic/basic_controller.js
@@ -188,12 +188,18 @@ var BasicController = AbstractController.extend(FieldManagerMixin, {
         // mutex-protected as commitChanges function of x2m has to be aware of
         // all final changes made to a row.
         var self = this;
-        this.savingDef = this.mutex.getUnlockedDef().then(function () {
-            return self.renderer.commitChanges(recordID || self.handle).then(function () {
+        var savingDef = $.Deferred();
+        this.savingDef = savingDef;
+
+        return this.mutex.getUnlockedDef()
+            .then(function () {
+                return self.renderer.commitChanges(recordID || self.handle);
+            })
+            .then(function () {
                 return self.mutex.exec(self._saveRecord.bind(self, recordID, options));
-            });
-        });
-        return this.savingDef;
+            })
+            .then(savingDef.resolve.bind(savingDef))
+            .fail(savingDef.resolve.bind(savingDef));
     },
     /**
      * @override