[FIX] mail, *: significantly reduce number of useless renders

* = hr_holidays, im_livechat, website_livechat

A huge amount of components where rendered for no reason, notably when typing a
new message (at every key press), which significantly slowed down the interface.

There were 2 causes to this number of renders:
- OWL rendering all children automatically, even if their props didn't change,
  unless `shouldUpdate` is overridden, which is now done.
- `useStore` selectors being way too generous in what they observed

task-2399731

closes odoo/odoo#62703

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

1 files changed, 6 insertions, 0 deletions

diff --git a/addons/mail/static/src/components/attachment/attachment.js b/addons/mail/static/src/components/attachment/attachment.js
index aef83877d18..9cdb08540cc 100644
--- a/addons/mail/static/src/components/attachment/attachment.js
+++ b/addons/mail/static/src/components/attachment/attachment.js
@@ -1,6 +1,7 @@
 odoo.define('mail/static/src/components/attachment/attachment.js', function (require) {
 'use strict';
 
+const useShouldUpdateBasedOnProps = require('mail/static/src/component_hooks/use_should_update_based_on_props/use_should_update_based_on_props.js');
 const useStore = require('mail/static/src/component_hooks/use_store/use_store.js');
 
 const components = {
@@ -16,6 +17,11 @@ class Attachment extends Component {
      */
     constructor(...args) {
         super(...args);
+        useShouldUpdateBasedOnProps({
+            compareDepth: {
+                attachmentLocalIds: 1,
+            },
+        });
         useStore(props => {
             const attachment = this.env.models['mail.attachment'].get(props.attachmentLocalId);
             return {