Return sanitised copy of description from artefactchooser (bug #736665)

When we are going to display an html artefact description outside a
tinymce window, in 'read-only' mode, we need it to be cleaned up by
the server in advance.  This patch adds returns a safe version of an
artefact description along with the original description, when
requested in the artefactchooser configuration.

Change-Id: I8725e56608214bba0a262de78e6dac8fcf5a4dd8
Signed-off-by: Richard Mansfield <richard.mansfield@catalyst.net.nz>

htdocs/artefact/internal/blocktype/textbox/lib.php

@@ -100,7 +100,7 @@ class PluginBlocktypeTextbox extends PluginBlocktype {
             'selectone'        => true,
             'selectjscallback' => 'updateTextContent',
             'getblocks'        => true,
-            'returnfields'     => array('id', 'title', 'description', 'editable'),
+            'returnfields'     => array('id', 'title', 'description', 'safedescription', 'editable'),
             'artefacttypes'    => array('html'),
             'template'         => 'artefact:internal:html-artefactchooser-element.tpl',
         );

htdocs/lib/view.php

@@ -2208,6 +2208,10 @@ class View {
                 if ($returnfields) {
                     $returnartefacts[$artefact->id] = array();
                     foreach ($returnfields as $f) {
+                        if ($f == 'safedescription') {
+                            $returnartefacts[$artefact->id]['safedescription'] = clean_html($artefact->description);
+                            continue;
+                        }
                         $returnartefacts[$artefact->id][$f] = $artefact->$f;
                     }
                 }