Create recursive symlink rather than storing it in version control.

Summary:
The presence of this recursive symlink was causing `ant lint` to yield
a warning, which is distracting.

Test Plan: Sandcastle builds.

test/com/facebook/buck/testutil/integration/ProjectWorkspace.java

diff --git a/test/com/facebook/buck/testutil/integration/ProjectWorkspace.java b/test/com/facebook/buck/testutil/integration/ProjectWorkspace.java
index 822fc1f..b65e29b 100644
--- a/test/com/facebook/buck/testutil/integration/ProjectWorkspace.java
+++ b/test/com/facebook/buck/testutil/integration/ProjectWorkspace.java
@@ -164,6 +164,13 @@
     return Files.toString(getFile(pathRelativeToProjectRoot), Charsets.UTF_8);
   }
 
+  /**
+   * @return the specified path resolved against the root of this workspace.
+   */
+  public Path resolve(Path pathRelativeToWorkspaceRoot) {
+    return destPath.resolve(pathRelativeToWorkspaceRoot);
+  }
+
   /** The result of running {@code buck} from the command line. */
   public static class ProcessResult {
     private final int exitCode;

test/com/facebook/buck/util/DirectoryTraversalTest.java

diff --git a/test/com/facebook/buck/util/DirectoryTraversalTest.java b/test/com/facebook/buck/util/DirectoryTraversalTest.java
index fb205e6..8556378 100644
--- a/test/com/facebook/buck/util/DirectoryTraversalTest.java
+++ b/test/com/facebook/buck/util/DirectoryTraversalTest.java
@@ -28,6 +28,7 @@
 
 import java.io.File;
 import java.io.IOException;
+import java.nio.file.Files;
 
 public class DirectoryTraversalTest {
   @Rule
@@ -39,6 +40,13 @@
         this, "directory_traversal_ignore_paths", temporaryFolder);
     workspace.setUp();
 
+    // Write a recursive symlink. We could store this in version control, but `ant lint` emits a
+    // warning about the recursive symlink.
+    Files.createDirectories(workspace.resolve(java.nio.file.Paths.get("loop/1")));
+    Files.createSymbolicLink(
+        workspace.resolve(java.nio.file.Paths.get("loop/1/upwards")),
+        java.nio.file.Paths.get("../"));
+
     // The workspace contains the following:
     //
     //   | path