[FIX/IMP] project,web: kanban cover image dialog

* Fix the grid display of images (use the column property)
* Use Dialog class
* Allow removing a cover image
* Add image selection before choosing it (or double click to choose)

+ add less mixins in web for columns property

1 files changed, 14 insertions, 0 deletions

diff --git a/addons/project/static/src/less/project_dashboard.less b/addons/project/static/src/less/project_dashboard.less
index 54b4087c974..36c48bb9cca 100644
--- a/addons/project/static/src/less/project_dashboard.less
+++ b/addons/project/static/src/less/project_dashboard.less
@@ -82,3 +82,17 @@
         }
     }
 }
+
+.o_kanban_task_cover_image {
+    .o-columns(200px, 4);
+    > img {
+        cursor: pointer;
+        margin-bottom: 1em;
+        border: 1px solid transparent;
+
+        &.o_selected {
+            border-color: @odoo-brand-secondary;
+            box-shadow: 0px 0px 2px 2px @odoo-brand-secondary;
+        }
+    }
+}