[REF] web, *: review the assets helpers organization

* survey, website_slides

While not changing their name or their amount, this commit reorganizes
the assets helpers to:

Avoid all file duplicates in different helpers
----------------------------------------------

Before, we had to put some files in different helpers, like our
bootstrap mixin overrides which were in the _assets_utils template and
in the _assets_bootstrap template.

Enforce the use of an helper when using bootstrap
-------------------------------------------------

Bootstrap functions, variables and mixins are now out of the
_assets_bootstrap template, which now only contains bootstrap css rules
and our bootstrap fixes and extensions.

Allow using the correct bootstrap utils in all assets
-----------------------------------------------------

In some assets (especially editor ones), we may want to use bootstrap
variables even though bootstrap is not included in those. This worked
before but using *default* bootstrap variables. Now, our overrides can
be properly included if necessary.

Note: this commit may also be a first step to allow for backend
bootstrap and frontend bootstrap to co-exist.

closes odoo/odoo#28204

1 files changed, 43 insertions, 0 deletions

diff --git a/addons/web/static/src/scss/import_bootstrap.scss b/addons/web/static/src/scss/import_bootstrap.scss
new file mode 100644
index 00000000000..d3d033a3575
--- /dev/null
+++ b/addons/web/static/src/scss/import_bootstrap.scss
@@ -0,0 +1,43 @@
+
+// This file is importing bootstrap. While a simple "import "bootstrap";"
+// should be enough, this does not allow overridding mixins/functions.
+// Overridding those is necessary for some of our need and allow to generate
+// more efficient CSS than adding more rules. This file instead copies the
+// content of the "bootstrap.scss" files but do not import functions, variables
+// and mixins which will be handled "by hand" in _assets_helpers.
+
+// @import "functions";
+// @import "variables";
+// @import "mixins";
+@import "root";
+@import "reboot";
+@import "type";
+@import "images";
+@import "code";
+@import "grid";
+@import "tables";
+@import "forms";
+@import "buttons";
+@import "transitions";
+@import "dropdown";
+@import "button-group";
+@import "input-group";
+@import "custom-forms";
+@import "nav";
+@import "navbar";
+@import "card";
+@import "breadcrumb";
+@import "pagination";
+@import "badge";
+@import "jumbotron";
+@import "alert";
+@import "progress";
+@import "media";
+@import "list-group";
+@import "close";
+@import "modal";
+@import "tooltip";
+@import "popover";
+@import "carousel";
+@import "utilities";
+@import "print";