MDL-57385 core: Set page layouts of non-mydashboard pages to standard

The following pages are using the "mydashboard" page layout:
* User preferences > Badges > Manage badges
* User preferences > Badges > Backpack settings
* User preferences > Repositories > Manage instances
* Private files
However, the "mydashboard" page layout should only be used for the user's
dashboard page. Changing these to use the "standard" page layout.

badges/mybackpack.php

@@ -50,7 +50,7 @@
 $title = get_string('backpackdetails', 'badges');
 $PAGE->set_title($title);
 $PAGE->set_heading(fullname($USER));
-$PAGE->set_pagelayout('mydashboard');
+$PAGE->set_pagelayout('standard');
 
 $backpack = $DB->get_record('badge_backpack', array('userid' => $USER->id));
 $badgescache = cache::make('core', 'externalbadges');

badges/mybadges.php

@@ -89,7 +89,7 @@
 $title = get_string('badges', 'badges');
 $PAGE->set_title($title);
 $PAGE->set_heading(fullname($USER));
-$PAGE->set_pagelayout('mydashboard');
+$PAGE->set_pagelayout('standard');
 
 // Include JS files for backpack support.
 badges_setup_backpack_js();

repository/manage_instances.php

@@ -91,7 +91,6 @@
         print_error('notyourinstances', 'repository');
     }
     $user = $USER;
-    $PAGE->set_pagelayout('mydashboard');
 } else {
     print_error('invalidcontext');
 }

user/files.php

@@ -48,7 +48,7 @@
 $PAGE->set_context($context);
 $PAGE->set_title($title);
 $PAGE->set_heading(fullname($USER));
-$PAGE->set_pagelayout('mydashboard');
+$PAGE->set_pagelayout('standard');
 $PAGE->set_pagetype('user-files');
 
 $maxbytes = $CFG->userquota;