[FIX] web: prevent useless discard dialog from showing up

Here is a scenario that could cause an issue:
- open a form view with a many2one
- click on edit button
- click on small external button for many2one. this opens a modal form
  view
- click on save in the modal (without changing anything)
- click on save in the main record
- exit form view. this opens a discard dialog

There were two issues here:
- saving the modal dialog automatically marks the many2one field as changed.
  This was necessary to force reloading the data, because editing a sub value
  in the modal form view could have changed the display_name of the manyone
  field.  However, this is not necessary when no change was done.
- when saving a record, the _isDirty flag was reset to false only if an
  actual rpc was done.  However, it may happen that the flag is set to
  dirty (for example, when modifying a value inside a many2one), but the
  main record has no changed fields.

In this commit, we also remove the on_save handler in the
formviewdialog.  This is a small refactoring in a stable version, but no code
currently use it, and I believe that it will make the code much easier
to maintain (the previous code was really awkward), so I think that the
tradeoff is acceptable.

1 files changed, 3 insertions, 1 deletions

diff --git a/addons/web/static/src/js/views/basic/basic_model.js b/addons/web/static/src/js/views/basic/basic_model.js
index 27a1e12ecfe..445967287bf 100644
--- a/addons/web/static/src/js/views/basic/basic_model.js
+++ b/addons/web/static/src/js/views/basic/basic_model.js
@@ -896,6 +896,9 @@ var BasicModel = AbstractModel.extend({
                 return def.resolve(changedFields);
             }
 
+            def.then(function () {
+                record._isDirty = false;
+            });
             // in the case of a write, only perform the RPC if there are changes to save
             if (method === 'create' || changedFields.length) {
                 var args = method === 'write' ? [[record.data.id], changes] : [changes];
@@ -917,7 +920,6 @@ var BasicModel = AbstractModel.extend({
 
                         // Erase changes as they have been applied
                         record._changes = {};
-                        record._isDirty = false;
 
                         // Update the data directly or reload them
                         if (shouldReload) {