Fixes for empty class and method bodies.

pkg/analyzer/test/services/data/cu_tests.data

 >>>
 class
 A
 {
 }
 <<<
 class A {
 }
 >>> dartbug.com/15876
 // fisk
@@ skipping 182 matching lines @@
   List<double> tangentImpulses = new List<double>(Settings.MAX_MANIFOLD_POINTS);
 
   ContactImpulse();
 }
 <<<
 class ContactImpulse {
   List<double> normalImpulses = new List<double>(Settings.MAX_MANIFOLD_POINTS);
   List<double> tangentImpulses = new List<double>(Settings.MAX_MANIFOLD_POINTS);
 
   ContactImpulse();
-}
+}
+>>> Empty class bodies may be on one line (or more)
+class A extends B { }
+<<<
+class A extends B {}
+>>>
+class A extends B {
+
+}
+<<<
+class A extends B {
+
+}