8268592: JDK-8262891 causes an NPE in Lint.augment

Reviewed-by: vromero

src/jdk.compiler/share/classes/com/sun/tools/javac/comp/Flow.java

@@ -1577,6 +1577,10 @@ public class Flow {
         public void visitClassDef(JCClassDecl tree) {
             //skip
         }
+        @Override
+        public void visitLambda(JCLambda tree) {
+            //skip
+        }
         public boolean isAlive() {
             return super.alive != Liveness.DEAD;
         }

test/langtools/tools/javac/T8268592/T8268592.java

@@ -0,0 +1,59 @@
+/*
+ * Copyright (c) 2021, Alphabet LLC. All rights reserved.
+ * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
+ *
+ * This code is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 only, as
+ * published by the Free Software Foundation.
+ *
+ * This code is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
+ * version 2 for more details (a copy is included in the LICENSE file that
+ * accompanied this code).
+ *
+ * You should have received a copy of the GNU General Public License version
+ * 2 along with this work; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
+ * or visit www.oracle.com if you need additional information or have any
+ * questions.
+ */
+
+/* @test
+ * @bug 8268592
+ * @summary JDK-8262891 causes an NPE in Lint.augment
+ * @compile T8268592.java
+ */
+
+import java.util.Collection;
+import java.util.function.Function;
+import java.util.function.Supplier;
+
+abstract class T {
+
+    abstract <T> T r(Function<String, Supplier<T>> x);
+
+    enum E {
+        ONE
+    }
+
+    abstract <T> Supplier<T> f(Function<T, Supplier<T>> x);
+
+    public void updateAcl(E e, Supplier<Void> v) {
+        r(
+                (String t) -> {
+                    switch (e) {
+                        case ONE:
+                            return f(
+                                    a -> {
+                                        Collection<String> m = null;
+                                        return v;
+                                    });
+                        default:
+                            return v;
+                    }
+                });
+    }
+}