Use append_to_html rather than function to_html: STRING

this is mainly to avoid creating useless intermediary strings.

draft/application/cms/src/modules/node/node_add_cms_execution.e

@@ -82,7 +82,7 @@ feature -- Execution
 								end
 								fd.apply_to_associated_form
 							end
-							b.append (f.to_html (theme))
+							f.append_to_html (theme, b)
 						end
 					else
 						set_title ("Access denied")

draft/application/cms/src/modules/node/node_edit_cms_execution.e

@@ -87,7 +87,7 @@ feature -- Execution
 								end
 								fd.apply_to_associated_form
 							end
-							b.append (f.to_html (theme))
+							f.append_to_html (theme, b)
 						end
 					else
 						b.append ("<h1>Access denied</h1>")