Import mobile-data-download code to AOSP.

All of the codes have been reviewed and approved by Android third party
review. CL: 18962326. This is the initial code dump.

Bug: 236694189

Test: mma
Change-Id: I6482a43cd23dbd420653c8bca82474295276c8d8

java/com/google/android/libraries/mobiledatadownload/GetFileGroupRequest.java

diff --git a/java/com/google/android/libraries/mobiledatadownload/GetFileGroupRequest.java b/java/com/google/android/libraries/mobiledatadownload/GetFileGroupRequest.java
new file mode 100644
index 0000000..bf117d5
--- /dev/null
+++ b/java/com/google/android/libraries/mobiledatadownload/GetFileGroupRequest.java
@@ -0,0 +1,65 @@
+/*
+ * Copyright 2022 Google LLC
+ *
+ * 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.google.android.libraries.mobiledatadownload;
+
+import android.accounts.Account;
+import com.google.auto.value.AutoValue;
+import com.google.common.base.Optional;
+import javax.annotation.concurrent.Immutable;
+
+/** Request to get a single file group. */
+@AutoValue
+@Immutable
+public abstract class GetFileGroupRequest {
+  GetFileGroupRequest() {}
+
+  public abstract String groupName();
+
+  public abstract Optional<Account> accountOptional();
+
+  public abstract Optional<String> variantIdOptional();
+
+  public abstract boolean preserveZipDirectories();
+
+  public static Builder newBuilder() {
+    return new AutoValue_GetFileGroupRequest.Builder().setPreserveZipDirectories(false);
+  }
+
+  /** Builder for {@link GetFileGroupRequest}. */
+  @AutoValue.Builder
+  public abstract static class Builder {
+    Builder() {}
+
+    /** Sets the name of the file group, which is required. */
+    public abstract Builder setGroupName(String groupName);
+
+    /** Sets the account that is associated to the file group, which is optional. */
+    public abstract Builder setAccountOptional(Optional<Account> accountOptional);
+
+    /** Sets the variant id associated with the group, which is optional. */
+    public abstract Builder setVariantIdOptional(Optional<String> variantIdOptional);
+
+    /**
+     * By default, MDD will scan the directories generated by unpacking zip files in a download
+     * transform and generate a ClientDataFile for each contained file. By default, MDD also hides
+     * the root directory. Setting this to true disables that behavior, and will simply return the
+     * directories as ClientDataFiles.
+     */
+    public abstract Builder setPreserveZipDirectories(boolean preserve);
+
+    public abstract GetFileGroupRequest build();
+  }
+}