fix: ♿ use context title if no banner title is available, remove aria-describedby when there is no description

Author: thomasmassmann

src/cusy/cms/browser/overrides/collective.behavior.banner.browser.banner.pt

@@ -2,15 +2,18 @@
     tal:define="banner view/find_banner|nothing"
     i18n:domain="collective.behavior.banner">
 
-  <aside id="portal-banner" class="banner" aria-labelledby="portal-banner-title" aria-describedby="portal-banner-description"
+  <aside id="portal-banner" class="banner" aria-label="" aria-labelledby="" aria-describedby=""
       tal:condition="python: banner"
       tal:define="has_image python:banner and 'banner_image' in banner;
                   has_url python:banner and 'banner_url' in banner;
                   has_fontcolor python:banner and 'banner_fontcolor' in banner;
                   fontcolor python:has_fontcolor and banner['banner_fontcolor'] + ' !important' or '#4d4d4d';
                   has_backgroundcolor python:banner and 'banner_backgroundcolor' in banner;
                   backgroundcolor python:has_backgroundcolor and 'background:' + banner['banner_backgroundcolor'] + ' !important' or ''"
-      tal:attributes="style backgroundcolor;">
+      tal:attributes="style backgroundcolor;
+                      aria-label python: banner.get('banner_title') and None or context.title;
+                      aria-labelledby python: banner.get('banner_title') and 'portal-banner-title' or None;
+                      aria-describedby python: banner.get('banner_description') and 'portal-banner-description' or None;">
     <div class="container">
       <div class="banner__container"
           tal:attributes="class python:'banner__container' if has_image else 'banner__container banner__container--no-image'">