Move WorkspaceFileValue to the lib.packages directory, since that's where WorkspaceFactory and the rest of its kind are. Also remove an unused method in WorkspaceFactory.

PiperOrigin-RevId: 231632979
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 f20e650..e11df3c 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
@@ -35,6 +35,7 @@
 import com.google.devtools.build.lib.packages.PackageFactory;
 import com.google.devtools.build.lib.packages.PackageFactory.EnvironmentExtension;
 import com.google.devtools.build.lib.packages.RuleClassProvider;
+import com.google.devtools.build.lib.packages.WorkspaceFileValue;
 import com.google.devtools.build.lib.pkgcache.PathPackageLocator;
 import com.google.devtools.build.lib.rules.repository.LocalRepositoryFunction;
 import com.google.devtools.build.lib.rules.repository.LocalRepositoryRule;
@@ -137,7 +138,7 @@
     RuleClassProvider ruleClassProvider = analysisMock.createRuleClassProvider();
     skyFunctions.put(SkyFunctions.WORKSPACE_AST, new WorkspaceASTFunction(ruleClassProvider));
     skyFunctions.put(
-        SkyFunctions.WORKSPACE_FILE,
+        WorkspaceFileValue.WORKSPACE_FILE,
         new WorkspaceFileFunction(
             ruleClassProvider,
             analysisMock