Fix desugared library jdk11 build

Change-Id: I4251d3d5338ee6da643b277971125639ebf7a232
diff --git a/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/jdk11/DesugaredLibraryJDK11Undesugarer.java b/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/jdk11/DesugaredLibraryJDK11Undesugarer.java
index b4cfa90..6e9d7ca 100644
--- a/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/jdk11/DesugaredLibraryJDK11Undesugarer.java
+++ b/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/jdk11/DesugaredLibraryJDK11Undesugarer.java
@@ -25,8 +25,6 @@
 
 public class DesugaredLibraryJDK11Undesugarer extends DesugaredLibraryTestBase {
 
-  private static final boolean ALLOW_CACHE = false;
-
   private static final Map<String, String> ownerMap =
       ImmutableMap.<String, String>builder()
           .put("java/util/DesugarTimeZone", "java/util/TimeZone")
@@ -50,15 +48,14 @@
     }
     Path desugaredLibJDK11Undesugared = Paths.get("build/libs/desugar_jdk_libs_11_undesugared.jar");
     if (Files.exists(desugaredLibJDK11Undesugared)) {
-      if (ALLOW_CACHE) {
         return desugaredLibJDK11Undesugared;
-      } else {
-        try {
-          Files.delete(desugaredLibJDK11Undesugared);
-        } catch (IOException e) {
-          throw new RuntimeException(e);
-        }
-      }
+    }
+    return generateUndesugaredJar(desugaredLibJDK11Undesugared);
+  }
+
+  private static synchronized Path generateUndesugaredJar(Path desugaredLibJDK11Undesugared) {
+    if (Files.exists(desugaredLibJDK11Undesugared)) {
+      return desugaredLibJDK11Undesugared;
     }
     OpenOption[] options =
         new OpenOption[] {StandardOpenOption.CREATE, StandardOpenOption.TRUNCATE_EXISTING};
diff --git a/tools/archive_desugar_jdk_libs.py b/tools/archive_desugar_jdk_libs.py
index 733e59b..91ad6b5 100755
--- a/tools/archive_desugar_jdk_libs.py
+++ b/tools/archive_desugar_jdk_libs.py
@@ -120,7 +120,7 @@
           checkout_dir, 'bazel-bin', 'src', 'share', 'classes', 'java', 'libjava.jar')
     else:
       library_jar = os.path.join(
-          checkout_dir, 'bazel-bin', 'jdk11', 'src', 'd8_java_base_selected.jar')
+          checkout_dir, 'bazel-bin', 'jdk11', 'src', 'd8_java_base_selected_with_addon.jar')
     maven_zip = os.path.join(
       checkout_dir,
       'bazel-bin',