Migrate ActionOwner to @AutoValue.

--
MOS_MIGRATED_REVID=138680612
diff --git a/src/main/java/com/google/devtools/build/lib/analysis/RuleContext.java b/src/main/java/com/google/devtools/build/lib/analysis/RuleContext.java
index ecb2e89..8f186d4 100644
--- a/src/main/java/com/google/devtools/build/lib/analysis/RuleContext.java
+++ b/src/main/java/com/google/devtools/build/lib/analysis/RuleContext.java
@@ -399,7 +399,7 @@
 
   @VisibleForTesting
   public static ActionOwner createActionOwner(Rule rule, BuildConfiguration configuration) {
-    return new ActionOwner(
+    return ActionOwner.create(
         rule.getLabel(),
         rule.getLocation(),
         configuration.getMnemonic(),