DrupalTest_TestCase::setUp() and the DrupalTest_TestCase::tearDown() should be protected not public

The visibility of the DrupalTest_TestCase::setUp() and DrupalTest_TestCase::tearDown() methods should be protected, so that they are able to be redeclared in child classes, but can also be called from child classes as parent::setUp() and parent::tearDown().

The declaration of these methods in the DrupalTest_TestCase should be changed to match that used in the DrupalTest_TestSuite. Essentially the DrupalTest_TestCase class setUp and tearDown method declarations should look like this:

class DrupalTest_TestCase extends PHPUnit_Framework_TestCase {
  protected function setUp() {
    parent::setUp();
  }

  protected function tearDown() {
    parent::tearDown();
  }
}