Enable flow documentation in external build

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=241934689

java/google/registry/util/BuildPathUtils.java

@@ -0,0 +1,40 @@
+// Copyright 2019 The Nomulus Authors. All Rights Reserved.
+//
+// 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 google.registry.util;
+
+import java.nio.file.Path;
+import java.nio.file.Paths;
+
+/** Utilities methods related to build path. */
+public final class BuildPathUtils {
+  // When we run the build from gradlew's directory, the current working directory would be
+  // ${projectRoot}/gradle/${subproject}. So, the project root is the grand parent of it.
+  private static final Path PROJECT_ROOT =
+      Paths.get(System.getProperty("test.projectRoot", "../../")).normalize();
+  private static final Path RESOURCES_DIR =
+      Paths.get(System.getProperty("test.resourcesDir", "build/resources/main")).normalize();
+
+  /** Returns the {@link Path} to the project root directory. */
+  public static Path getProjectRoot() {
+    return PROJECT_ROOT;
+  }
+
+  /** Returns the {@link Path} to the resources directory. */
+  public static Path getResourcesDir() {
+    return RESOURCES_DIR;
+  }
+
+  private BuildPathUtils() {}
+}