Add AIDL interface and puller implementation for automotive devices.

Changes:
  - Adds hidden ICarStatsService AIDL API.
  - Adds CarStatsPuller for pulling atoms from ICarStatsService.
  - Pulls VmsClientStats via CarStatsPuller.

Bug: 141697665
Test: Manual testing on hawk using statsd_testdrive
Change-Id: I44e104d430f64b1bd3dce96e9749df79ab3d2fbf
Merged-In: I44e104d430f64b1bd3dce96e9749df79ab3d2fbf
(cherry picked from commit 9dc13578f7)

core/java/Android.bp

@@ -7,3 +7,8 @@ filegroup {
     name: "IDropBoxManagerService.aidl",
     srcs: ["com/android/internal/os/IDropBoxManagerService.aidl"],
 }
+
+filegroup {
+    name: "ICarStatsService.aidl",
+    srcs: ["com/android/internal/car/ICarStatsService.aidl"],
+}

core/java/com/android/internal/car/ICarStatsService.aidl

@@ -0,0 +1,31 @@
+/*
+ * Copyright (C) 2019 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.internal.car;
+
+import android.os.StatsLogEventWrapper;
+
+/**
+ * Interface for pulling statsd atoms from automotive devices.
+ *
+ * @hide
+ */
+interface ICarStatsService {
+    /**
+     * Pull the specified atom. Results will be sent to statsd when complete.
+     */
+    StatsLogEventWrapper[] pullData(int atomId);
+}