misc: make card linked to page update page title (#74073)

@@ -1686,0 +1687,4 @@
+            card_data.get('digest') or card_data.get('digests')
+        ):
+            # card linked to page, set attribute to have card title in page <title>
+            page_title_from_cell = card_data.get('digest')

@@ -1686,0 +1696,4 @@
+                if card_data.get('digests', {}).get(digest_name):
+                    page_title_from_cell = card_data['digests'][digest_name]
+            if page_title_from_cell:
+                custom_context['request'].page_title_from_cell = page_title_from_cell

@@ -34,0 +36,4 @@
+                  if (document.original_title === undefined) {
+                      document.original_title = document.title
+                  }
+                  document.title = page_title + ' | ' + document.original_title;

@@ -203,0 +202,4 @@
+    response = HttpResponse(response_content, content_type='text/html')
+    if hasattr(request, 'page_title_from_cell'):
+        # cell request a change to page title, pass info in response header
+        response.headers['X-Page-Title'] = request.page_title_from_cell

@@ -619,0 +622,4 @@
+    response_content = loader.render_to_string(template_name, ctx, request)
+    if hasattr(request, 'page_title_from_cell'):
+        # a synchronous cell requested a change to page <title>, do it.
+        response_content = response_content.replace('<title>', f'<title>{request.page_title_from_cell} | ', 1)