Migrate some code to java 8 types where possible.
Skipped methods such as Iterables.filter which only take the guava type.

PiperOrigin-RevId: 324391526
diff --git a/src/test/java/com/google/devtools/build/lib/skyframe/PackageLookupFunctionTest.java b/src/test/java/com/google/devtools/build/lib/skyframe/PackageLookupFunctionTest.java
index 992197c..034194f 100644
--- a/src/test/java/com/google/devtools/build/lib/skyframe/PackageLookupFunctionTest.java
+++ b/src/test/java/com/google/devtools/build/lib/skyframe/PackageLookupFunctionTest.java
@@ -17,7 +17,6 @@
 import static com.google.common.truth.Truth.assertThat;
 import static com.google.devtools.build.skyframe.EvaluationResultSubjectFactory.assertThatEvaluationResult;
 
-import com.google.common.base.Optional;
 import com.google.common.collect.ImmutableList;
 import com.google.common.collect.ImmutableMap;
 import com.google.common.collect.ImmutableSet;
@@ -67,6 +66,7 @@
 import java.util.HashMap;
 import java.util.List;
 import java.util.Map;
+import java.util.Optional;
 import java.util.UUID;
 import java.util.concurrent.atomic.AtomicBoolean;
 import java.util.concurrent.atomic.AtomicReference;
@@ -182,7 +182,7 @@
     RepositoryDelegatorFunction.DEPENDENCY_FOR_UNCONDITIONAL_FETCHING.set(
         differencer, RepositoryDelegatorFunction.DONT_FETCH_UNCONDITIONALLY);
     RepositoryDelegatorFunction.RESOLVED_FILE_INSTEAD_OF_WORKSPACE.set(
-        differencer, Optional.<RootedPath>absent());
+        differencer, Optional.empty());
   }
 
   protected PackageLookupValue lookupPackage(String packageName) throws InterruptedException {