Remove MANAGED characteristic

src/java.base/share/classes/java/lang/Thread.java

@@ -719,12 +719,6 @@ public static Builder builder() {
          */
         Builder uncaughtExceptionHandler(UncaughtExceptionHandler ueh);
 
-        /**
-         * The thread is <em>managed</em>.
-         * @return this builder
-         */
-        Builder managed();
-
         /**
          * Sets the task for the thread to run.
          * @param task the task to run
@@ -882,12 +876,6 @@ public Builder uncaughtExceptionHandler(UncaughtExceptionHandler ueh) {
             return this;
         }
 
-        @Override
-        public Builder managed() {
-            // TDB
-            return this;
-        }
-
         @Override
         public Thread build() {
             Runnable task = this.task;
@@ -1384,15 +1372,8 @@ public Thread(ThreadGroup group, Runnable task, String name,
      */
     public static final int INHERIT_THREAD_LOCALS = 1 << 2;
 
-    /**
-     * Characteristic value signifying that the thread is <em>managed.</em>
-     *
-     * @since 99
-     */
-    public static final int MANAGED = 1 << 3;
-
     private static int validCharacteristics() {
-        return (VIRTUAL | NO_THREAD_LOCALS | INHERIT_THREAD_LOCALS | MANAGED);
+        return (VIRTUAL | NO_THREAD_LOCALS | INHERIT_THREAD_LOCALS);
     }
 
     private static void checkCharacteristics(int characteristics) {