Adds an enum to describe how PackageLookupFunction should handle package labels
which cross into a sub-repository. Part of #1592.

--
MOS_MIGRATED_REVID=135931868
diff --git a/src/test/java/com/google/devtools/build/lib/skyframe/FileFunctionTest.java b/src/test/java/com/google/devtools/build/lib/skyframe/FileFunctionTest.java
index 323fa84..5257324 100644
--- a/src/test/java/com/google/devtools/build/lib/skyframe/FileFunctionTest.java
+++ b/src/test/java/com/google/devtools/build/lib/skyframe/FileFunctionTest.java
@@ -40,6 +40,7 @@
 import com.google.devtools.build.lib.events.NullEventHandler;
 import com.google.devtools.build.lib.events.StoredEventHandler;
 import com.google.devtools.build.lib.pkgcache.PathPackageLocator;
+import com.google.devtools.build.lib.skyframe.PackageLookupFunction.CrossRepositoryLabelViolationStrategy;
 import com.google.devtools.build.lib.testutil.ManualClock;
 import com.google.devtools.build.lib.testutil.TestConstants;
 import com.google.devtools.build.lib.testutil.TestRuleClassProvider;
@@ -142,7 +143,8 @@
                 .put(
                     SkyFunctions.PACKAGE_LOOKUP,
                     new PackageLookupFunction(
-                        new AtomicReference<>(ImmutableSet.<PackageIdentifier>of())))
+                        new AtomicReference<>(ImmutableSet.<PackageIdentifier>of()),
+                        CrossRepositoryLabelViolationStrategy.ERROR))
                 .put(
                     SkyFunctions.WORKSPACE_AST,
                     new WorkspaceASTFunction(TestRuleClassProvider.getRuleClassProvider()))