Bug: Skylark performs action consistency check even if actions are dropped.

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MOS_MIGRATED_REVID=113524029
diff --git a/src/main/java/com/google/devtools/build/lib/analysis/CachingAnalysisEnvironment.java b/src/main/java/com/google/devtools/build/lib/analysis/CachingAnalysisEnvironment.java
index ca3e621..bfdd8b9 100644
--- a/src/main/java/com/google/devtools/build/lib/analysis/CachingAnalysisEnvironment.java
+++ b/src/main/java/com/google/devtools/build/lib/analysis/CachingAnalysisEnvironment.java
@@ -157,6 +157,9 @@
 
   @Override
   public ImmutableSet<Artifact> getOrphanArtifacts() {
+    if (!allowRegisteringActions) {
+      return ImmutableSet.<Artifact>of();
+    }
     return ImmutableSet.copyOf(getOrphanArtifactMap().keySet());
   }