Before this commit the close button cross/multiply character was wrongly
translated in some languages (e.g. Spanish)

After this commit the close button cross/multiply character is not a
translatable text anymore

https://github.com/odoo/odoo/pull/60268
task-2365792

closes odoo/odoo#60268

Signed-off-by: Jérémy Kersten (jke) <jke@openerp.com>

adds _isCustomResource method which will check whether resource is custom or
not, this method checks for JS and SCSS resource, if resource is custom then
do not show "No Update" warning inside ace editor.

task-2167570

closes odoo/odoo#44536

Related: odoo/enterprise#8368
Signed-off-by: Damien Bouvy (dbo) <dbo@odoo.com>
Co-authored-by: Mohammed Shekha <msh@odoo.com>

The text was gray on gray... it is now forced to white.

Part of https://github.com/odoo/odoo/pull/34422
task-2026299

- End of list in image library
- Title add menu item
- Warning message in html/css/js editor
- Wording building block sections

Part of https://github.com/odoo/odoo/pull/30986
task-1939869

* web_editor

Currently, when an user wants to edit the css of its website, he has
access to lots of files and, in debug mode, to even more files. While
the feature is nice for people who know what they are doing, a lambda
person can easily break its website by changing the wrong files. Also,
nothing warns the user that the files that are edited will never receive
updates anymore (unless if they are reset). The goal is to prevent
those behavior while still allowing the add custom css. Another goal
is to be able to *add* custom javascript.

Custom files created for the user:
SCSS: user_custom_rules.scss, user_custom_bootstrap_overridden.scss
JS: user_custom_javascript.js

See https://github.com/odoo/odoo/pull/29999
task-1919350

In a previous commit, we removed the use of the 'btn-sm' classes as we
used it everywhere for default-size buttons instead of customizing the
size of those default-size buttons directly.

This commit proves it was even more necessary as the 'btn-xs' class does
not exist anymore in BS4 and we so can use the 'btn-sm' class instead.

Before this commit, Odoo used checkboxes in three different ways:

- A simple <input type="checkbox"/>, mainly in the frontend. The style
  is browser dependant.

- Same as above but with the BS3, checkbox structure. The style is still
  the same, but the alignement is supposed to be better (which is not
  always the case).

- The Odoo official structure:
	```
	<div class="o_checkbox">
	    <input type="checkbox"/>
	    <span/>
	</div>
	```
  which allows to have a cross-browser checkbox style and correct
  alignements.

The goal after this commit is to only use the BS4 *custom* checkbox
structure to achieve the same goal as our official structure (and
remove that one):

```
<div class="custom-control custom-checkbox">
  <input type="checkbox" class="custom-control-input" id="customCheck1">
  <label class="custom-control-label" for="customCheck1">...</label>
</div>
```

/!\ Labels are now required (use a zero-width space if necessary)

- The dropdown structure was simplified, allowing to get rid of the
  3-levels structure induced by <ul/> elements and dropdowns can now
  contain anything. The class 'dropdown-item' is now mandatory for
  each dropdown clickable element. The class 'dropdown-item-text' can
  be used to add same padding and style but without making the element
  have a clickable look.

- Dividers now use the class 'dropdown-divider'

- The way dropdowns are opened and hidden also changed (before the
  'open' class was added on the `.dropdown-menu` parent, now the
  'show' class is added on both the `.dropdown-menu` parent and the
  `.dropdown-menu` itself).

- JS-wise, no click event handlers can be put on `.dropdown-toggle`
  elements anymore (instead, use handlers for dropdown events).

- Carets are automatically put on `.dropdown-toggle` elements, so this
  commit replaces the `.caret` elements with this. This feature was
  possible to disable but would prevent us from adding a caret with
  scss. Also, this simplifies the DOM. The 'o-no-caret' class was also
  introduced to allow using the 'dropdown-toggle' class on non-caret
  elements.

- Also adapt the scss to use $caret-width instead of $caret-width-base

BS4 "btn-default" class was replaced with "btn-secondary", which makes
more sense.