MDL-39474 introduce $CFG->debugdeveloper and cleanup $CFG init

lib/phpunit/bootstrap.php

@@ -198,6 +198,7 @@ unset($productioncfg);
 
 // force the same CFG settings in all sites
 $CFG->debug = (E_ALL | E_STRICT); // can not use DEBUG_DEVELOPER yet
+$CFG->debugdeveloper = true;
 $CFG->debugdisplay = 1;
 error_reporting($CFG->debug);
 ini_set('display_errors', '1');

lib/phpunit/classes/advanced_testcase.php

@@ -248,7 +248,8 @@ abstract class advanced_testcase extends PHPUnit_Framework_TestCase {
     }
 
     /**
-     * Clear all previous debugging messages in current test.
+     * Clear all previous debugging messages in current test
+     * and revert to default DEVELOPER_DEBUG level.
      */
     public function resetDebugging() {
         phpunit_util::reset_debugging();

lib/phpunit/classes/util.php

@@ -594,6 +594,7 @@ class phpunit_util extends testing_util {
      */
     public static function reset_debugging() {
         self::$debuggings = array();
+        set_debugging(DEBUG_DEVELOPER);
     }
 
     /**

lib/phpunit/tests/advanced_test.php

@@ -65,9 +65,10 @@ class core_phpunit_advanced_testcase extends advanced_testcase {
         $debuggings = $this->getDebuggingMessages();
         $this->assertEquals(0, count($debuggings));
 
-        $CFG->debug = DEBUG_NONE;
+        set_debugging(DEBUG_NONE);
         debugging('hokus');
         $this->assertDebuggingNotCalled();
+        set_debugging(DEBUG_DEVELOPER);
     }
 
     public function test_set_user() {