MDL-39491 Fix order of Workshop submission text processing

The order of format_text() and file_rewrite_pluginfile_urls() is
important to make filters work correctly.

mod/workshop/renderer.php

@@ -132,9 +132,9 @@ protected function render_workshop_submission(workshop_submission $submission) {
 
         $o .= $this->output->container_end(); // end of header
 
-        $content = format_text($submission->content, $submission->contentformat, array('overflowdiv'=>true));
-        $content = file_rewrite_pluginfile_urls($content, 'pluginfile.php', $this->page->context->id,
+        $content = file_rewrite_pluginfile_urls($submission->content, 'pluginfile.php', $this->page->context->id,
                                                         'mod_workshop', 'submission_content', $submission->id);
+        $content = format_text($content, $submission->contentformat, array('overflowdiv'=>true));
         if (!empty($content)) {
             if (!empty($CFG->enableplagiarism)) {
                 require_once($CFG->libdir.'/plagiarismlib.php');
@@ -232,9 +232,9 @@ protected function render_workshop_example_submission(workshop_example_submissio
         $o .= $this->output->heading(format_string($example->title), 3, 'title');
         $o .= $this->output->container_end(); // end of header
 
-        $content = format_text($example->content, $example->contentformat, array('overflowdiv'=>true));
-        $content = file_rewrite_pluginfile_urls($content, 'pluginfile.php', $this->page->context->id,
+        $content = file_rewrite_pluginfile_urls($example->content, 'pluginfile.php', $this->page->context->id,
                                                         'mod_workshop', 'submission_content', $example->id);
+        $content = format_text($content, $example->contentformat, array('overflowdiv'=>true));
         $o .= $this->output->container($content, 'content');
 
         $o .= $this->helper_submission_attachments($example->id, 'html');