Add TypeAccessor to api/meta for objects without Object/ListMeta

Adding objects that have TypeMeta (use runtime.Scheme) but do not
expose ObjectMeta/ListMeta (because they are not Kube API objects)
and wanted to get the simpler access path for in memory objects.

pkg/api/meta/meta_test.go

@@ -79,6 +79,17 @@ func TestGenericTypeMeta(t *testing.T) {
 		t.Errorf("expected %v, got %v", e, a)
 	}
 
+	typeAccessor, err := TypeAccessor(&j)
+	if err != nil {
+		t.Fatalf("unexpected error: %v", err)
+	}
+	if e, a := "a", accessor.APIVersion(); e != a {
+		t.Errorf("expected %v, got %v", e, a)
+	}
+	if e, a := "b", accessor.Kind(); e != a {
+		t.Errorf("expected %v, got %v", e, a)
+	}
+
 	accessor.SetNamespace("baz")
 	accessor.SetName("bar")
 	accessor.SetUID("other")
@@ -109,6 +120,15 @@ func TestGenericTypeMeta(t *testing.T) {
 	if e, a := "google.com", j.SelfLink; e != a {
 		t.Errorf("expected %v, got %v", e, a)
 	}
+
+	typeAccessor.SetAPIVersion("d")
+	typeAccessor.SetKind("e")
+	if e, a := "d", j.APIVersion; e != a {
+		t.Errorf("expected %v, got %v", e, a)
+	}
+	if e, a := "e", j.Kind; e != a {
+		t.Errorf("expected %v, got %v", e, a)
+	}
 }
 
 type InternalTypeMeta struct {