[Media ML] Remove using android.os.HandlerExecutor

Copy over the class to com.android.server.media package.
See ag/9375221 for reference.

Bug: 161416780
Test: build
Change-Id: I09d9fa69c143b00c2918e45604c169ea8b82d087

services/core/java/com/android/server/media/HandlerExecutor.java

@@ -0,0 +1,45 @@
+/*
+ * Copyright 2020 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.android.server.media;
+
+import android.annotation.NonNull;
+import android.os.Handler;
+
+import java.util.Objects;
+import java.util.concurrent.Executor;
+import java.util.concurrent.RejectedExecutionException;
+
+/**
+ * An adapter {@link Executor} that posts all executed tasks onto the given
+ * {@link Handler}.
+ *
+ * @hide
+ */
+public class HandlerExecutor implements Executor {
+    private final Handler mHandler;
+
+    public HandlerExecutor(@NonNull Handler handler) {
+        mHandler = Objects.requireNonNull(handler);
+    }
+
+    @Override
+    public void execute(Runnable command) {
+        if (!mHandler.post(command)) {
+            throw new RejectedExecutionException(mHandler + " is shutting down");
+        }
+    }
+}

services/core/java/com/android/server/media/MediaSession2Record.java

@@ -20,7 +20,6 @@ import android.media.MediaController2;
 import android.media.Session2CommandGroup;
 import android.media.Session2Token;
 import android.os.Handler;
-import android.os.HandlerExecutor;
 import android.os.Looper;
 import android.os.ResultReceiver;
 import android.os.UserHandle;