[FIX] web_editor: do not cache promise forever pending

The wysiwyg component uses the ColorPalette, and gives it a callback
in props (getTemplate). This callback does an orm service call and
thus returns a promise. It is called by the ColorPalette in its
willStart, and the result (the promise) is stored in the closure of
the js module defining the ColorPalette, s.t. subsequent willStart
directly reuse the promise instead of calling getTemplate.

The problem is that the orm service (when defined via useService)
is bound to the component using it. If the component is destroyed
before the rpc returns, the promise is kept pending forever. It
might thus happen that the ColorPalette stored a promise forever
pending, leading to a screen never loading. It was for instance
the case in Invoices (list view), when you clicked on a record:
the form view might never open. In this situation, two renderings
where initiated, the first one triggered the rpc, and the second
one cancelled the first one, making the promise being pending
forever.

This commit bypasses useService to use the orm, which isn't the
best solution but it's the easiest and fastest one. Ideally, this
rpc should be done by a service, which could keep the promise in
its closure. However, a lot of test suites would need to be adapted
to make the service available for its tests.

closes odoo/odoo#129974

Signed-off-by: Géry Debongnie <ged@odoo.com>

addons/web_editor/static/src/js/wysiwyg/wysiwyg.js

@@ -2956,11 +2956,11 @@ export class Wysiwyg extends Component {
     }
 
     _getColorpickerTemplate() {
-        return this.orm.call(
+        return this.env.services.orm.call(
             'ir.ui.view',
             'render_public_asset',
             ['web_editor.colorpicker', {}]
-        )
+        );
     }
 
     // -----------------------------------------------------------------------------