To replicate this issue:

1. Login on 2.7 and go to admin/index
2. Now, checkout master
3. Now, click 'Notifcations'
4. Notice the error below

Note: This doesn't happen when checking out the master codebase before logging in, so I've removed '3.3 must fix'

ERROR: relation "mdl_tool_usertours_tours" does not exist
LINE 2: FROM mdl_tool_usertours_tours t
^
SELECT t.*
FROM mdl_tool_usertours_tours t
WHERE t.enabled = 1
AND t.id IN (SELECT s.tourid FROM mdl_tool_usertours_steps s GROUP BY s.tourid)
ORDER BY t.sortorder ASC
[array (
)]
Error code: dmlreadexception

Stack trace:

• line 486 of /lib/dml/moodle_database.php: dml_read_exception thrown
• line 242 of /lib/dml/pgsql_native_moodle_database.php: call to moodle_database->query_end()
• line 776 of /lib/dml/pgsql_native_moodle_database.php: call to pgsql_native_moodle_database->query_end()
• line 69 of /admin/tool/usertours/classes/cache.php: call to pgsql_native_moodle_database->get_records_sql()
• line 82 of /admin/tool/usertours/classes/cache.php: call to tool_usertours\cache::get_enabled_tourdata()
• line 580 of /admin/tool/usertours/classes/manager.php: call to tool_usertours\cache::get_matching_tourdata()
• line 565 of /admin/tool/usertours/classes/manager.php: call to tool_usertours\manager::get_matching_tours()
• line 505 of /admin/tool/usertours/classes/helper.php: call to tool_usertours\manager::get_current_tour()
• line 75 of /admin/tool/usertours/lib.php: call to tool_usertours\helper::bootstrap()
• line 1180 of /lib/outputrenderers.php: call to tool_usertours_before_footer()
• line ? of unknownfile: call to core_renderer->footer()
• line 437 of /lib/outputrenderers.php: call to call_user_func_array()
• line 153 of /admin/renderer.php: call to plugin_renderer_base->__call()
• line 153 of /admin/renderer.php: call to core_admin_renderer->footer()
• line 357 of /admin/index.php: call to core_admin_renderer->upgrade_confirm_page()