Refactoring: makes the code simpler by deleting Metadata and InputArtifactData.

(minor) ActionFS now implements MetadataProvider.getInput

PiperOrigin-RevId: 199575194
diff --git a/src/main/java/com/google/devtools/build/lib/skyframe/RecursiveFilesystemTraversalFunction.java b/src/main/java/com/google/devtools/build/lib/skyframe/RecursiveFilesystemTraversalFunction.java
index 2948e4e..a03f879 100644
--- a/src/main/java/com/google/devtools/build/lib/skyframe/RecursiveFilesystemTraversalFunction.java
+++ b/src/main/java/com/google/devtools/build/lib/skyframe/RecursiveFilesystemTraversalFunction.java
@@ -18,6 +18,9 @@
 import com.google.common.base.Verify;
 import com.google.common.collect.Collections2;
 import com.google.devtools.build.lib.actions.Artifact;
+import com.google.devtools.build.lib.actions.FileArtifactValue;
+import com.google.devtools.build.lib.actions.FileStateValue;
+import com.google.devtools.build.lib.actions.FileValue;
 import com.google.devtools.build.lib.collect.nestedset.NestedSet;
 import com.google.devtools.build.lib.collect.nestedset.NestedSetBuilder;
 import com.google.devtools.build.lib.events.Event;