MDL-71955 h5p: ensure embedded player sets up $PAGE correctly.

For module context, it should set the current cm and course to
ensure consistency in navigation API.

h5p/embed.php

@@ -51,7 +51,15 @@
 
 if (empty($messages->error) && empty($messages->exception)) {
     // Configure page.
-    $PAGE->set_context($h5pplayer->get_context());
+    $context = $h5pplayer->get_context();
+    if ($context instanceof context_module) {
+        [$course, $cm] = get_course_and_cm_from_cmid($context->instanceid);
+        $PAGE->set_cm($cm, $course);
+        $PAGE->activityheader->disable();
+    } else {
+        $PAGE->set_context($context);
+    }
+
     $PAGE->set_title($h5pplayer->get_title());
     $PAGE->set_heading($h5pplayer->get_title());