Don't verify the visibility of a method's declaring class.

I would not expect FrameworkMethod.validatePublicVoid(...) to test
visibility of the declaring class. Since the last commit the runner
itself verifies that a test class is public. Hence we can safely remove
this validation from FrameworkMethod.

This fixes #749 (JUnit cannot be build with JDK 8), too.

src/main/java/org/junit/runners/model/FrameworkMethod.java

@@ -3,7 +3,6 @@
 import java.lang.annotation.Annotation;
 import java.lang.reflect.InvocationTargetException;
 import java.lang.reflect.Method;
-import java.lang.reflect.Modifier;
 import java.lang.reflect.Type;
 import java.util.List;
 
@@ -91,9 +90,6 @@ public void validatePublicVoid(boolean isStatic, List<Throwable> errors) {
             String state = isStatic ? "should" : "should not";
             errors.add(new Exception("Method " + fMethod.getName() + "() " + state + " be static"));
         }
-        if (!Modifier.isPublic(getDeclaringClass().getModifiers())) {
-            errors.add(new Exception("Class " + getDeclaringClass().getName() + " should be public"));
-        }
         if (!isPublic()) {
             errors.add(new Exception("Method " + fMethod.getName() + "() should be public"));
         }

src/test/java/org/junit/tests/AllTests.java

@@ -99,7 +99,6 @@
 import org.junit.tests.running.methods.TimeoutTest;
 import org.junit.tests.validation.BadlyFormedClassesTest;
 import org.junit.tests.validation.FailedConstructionTest;
-import org.junit.tests.validation.InaccessibleBaseClassTest;
 import org.junit.tests.validation.ValidationTest;
 import org.junit.validator.PublicClassValidatorTest;
 
@@ -143,7 +142,6 @@
         JUnit38ClassRunnerTest.class,
         SystemExitTest.class,
         JUnitCoreReturnsCorrectExitCodeTest.class,
-        InaccessibleBaseClassTest.class,
         SuiteMethodTest.class,
         BadlyFormedClassesTest.class,
         IgnoreClassTest.class,