Teach FakeSubincludeTarget its package, because rdeps wants it

While evaluating the transitive closure of the universe, if the
universe contains the buildfiles of a package with a subinclude, the
RdepsFunction would ask a FakeSubincludeTarget for its package.

Prior to this change, this would result in a crash. Now,
FakeSubincludeTargets remember the package they belong to.

--
MOS_MIGRATED_REVID=95212925
diff --git a/src/main/java/com/google/devtools/build/lib/query2/BlazeQueryEnvironment.java b/src/main/java/com/google/devtools/build/lib/query2/BlazeQueryEnvironment.java
index e36014c..79ff3a9 100644
--- a/src/main/java/com/google/devtools/build/lib/query2/BlazeQueryEnvironment.java
+++ b/src/main/java/com/google/devtools/build/lib/query2/BlazeQueryEnvironment.java
@@ -361,7 +361,7 @@
   }
 
   private Node<Target> getSubincludeTarget(final Label label, Package pkg) {
-    return getNode(new FakeSubincludeTarget(label, pkg.getBuildFile().getLocation()));
+    return getNode(new FakeSubincludeTarget(label, pkg));
   }
 
   @Override