Create basic reentrant ClasspathFetcher targetprep

This will take over the responsibilities of StrictJavaPackagesTest's
setup code, and by fetching and processing all classpath data, as
defined in go/stricter-java-packages-test .

Test: atest ClasspathFetcherTest
Bug: 254647172
Change-Id: I93d2651994f7602d60ae91ca2401b83ae8c57baf

java/com/android/modules/targetprep/Android.bp

@@ -0,0 +1,27 @@
+// Copyright (C) 2022 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 {
+    default_applicable_licenses: ["Android-Apache-2.0"],
+}
+java_library_host {
+    name: "ClasspathFetcher",
+    srcs: ["ClasspathFetcher.java"],
+    libs: [
+        "cts-tradefed",
+        "tradefed",
+        "compatibility-host-util",
+        "androidx.annotation_annotation",
+    ],
+}