Add an --experimental_disable_jvm flag.

--
MOS_MIGRATED_REVID=101457236
diff --git a/src/main/java/com/google/devtools/build/lib/analysis/BuildView.java b/src/main/java/com/google/devtools/build/lib/analysis/BuildView.java
index 7ce8c04..a64e031 100644
--- a/src/main/java/com/google/devtools/build/lib/analysis/BuildView.java
+++ b/src/main/java/com/google/devtools/build/lib/analysis/BuildView.java
@@ -525,6 +525,10 @@
       return error;
     }
 
+    public boolean hasError() {
+      return error != null;
+    }
+
     /**
      * Returns the action graph.
      */