8003280: Add lambda tests

Turn on lambda expression, method reference and default method support

Reviewed-by: jjg

langtools/test/tools/javac/lambda/SourceLevelTest.java

@@ -0,0 +1,23 @@
+/*
+ * @test /nodynamiccopyright/
+ * @bug 8003280
+ * @summary Add lambda tests
+ *  check that lambda features are not enabled with source < 8
+ * @compile/fail/ref=SourceLevelTest.out -XDrawDiagnostics -source 7 SourceLevelTest.java
+ */
+
+class SourceLevelTest {
+    interface I {
+        default void m() { SourceLevelTest.impl(this); }
+    }
+
+    interface SAM {
+        void m();
+    }
+
+    SAM s1 = () -> { };
+    SAM s2 = this::m;
+
+    static void impl(I i) {}
+    void m() {}
+}