[FIX] mail: ignore `undefined` in JS fields create/write

Passing a field containing `undefined` should lead to the same result as not
passing the field.

Fields that relied on `undefined` as a value have been changed to use the newly
introduced `clear` command, that resets a field to its default value (often
that is equal to `undefined`).

task-2336491

closes odoo/odoo#58308

X-original-commit: b18824485483564d2ab80f41914a3548aa528ae0
Signed-off-by: Alexandre Kühn (aku) <aku@odoo.com>

1 files changed, 7 insertions, 3 deletions

diff --git a/addons/mail/static/src/models/thread_view/thread_view.js b/addons/mail/static/src/models/thread_view/thread_view.js
index 599a99cc936..f2c64dabe2c 100644
--- a/addons/mail/static/src/models/thread_view/thread_view.js
+++ b/addons/mail/static/src/models/thread_view/thread_view.js
@@ -4,6 +4,7 @@ odoo.define('mail/static/src/models/thread_view/thread_view.js', function (requi
 const { registerNewModel } = require('mail/static/src/model/model_core.js');
 const { RecordDeletedError } = require('mail/static/src/model/model_errors.js');
 const { attr, many2many, many2one, one2one } = require('mail/static/src/model/model_field.js');
+const { clear } = require('mail/static/src/model/model_field_command.js');
 
 function factory(dependencies) {
 
@@ -77,9 +78,13 @@ function factory(dependencies) {
          */
         _computeThreadCacheInitialScrollPosition() {
             if (!this.threadCache) {
-                return;
+                return clear();
+            }
+            const threadCacheInitialScrollPosition = this.threadCacheInitialScrollPositions[this.threadCache.localId];
+            if (threadCacheInitialScrollPosition !== undefined) {
+                return threadCacheInitialScrollPosition;
             }
-            return this.threadCacheInitialScrollPositions[this.threadCache.localId];
+            return clear();
         }
 
         /**
@@ -102,7 +107,6 @@ function factory(dependencies) {
                     }
                 });
             }
-            return true;
         }
 
         /**