Refactoring: uses OutputService for ActionFileSystem injection

Moves more Action-oriented from skyframe package, which has become very unwieldy, to action package. This is needed to avoid circular dependencies caused when build-base is needed for skyframe.

PiperOrigin-RevId: 200996982
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 a03f879..d91e46e 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 +18,7 @@
 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.ArtifactSkyKey;
 import com.google.devtools.build.lib.actions.FileArtifactValue;
 import com.google.devtools.build.lib.actions.FileStateValue;
 import com.google.devtools.build.lib.actions.FileValue;