Enable new vector access nodes as default.

com.oracle.truffle.r.runtime/src/com/oracle/truffle/r/runtime/FastROptions.java

@@ -77,7 +77,7 @@ public class FastROptions {
     public static final boolean InvisibleArgs = parseBooleanOption("InvisibleArgs", true, "Argument writes do not trigger state transitions");
     public static final boolean NewStateTransition = parseBooleanOption("NewStateTransition", false, "Experimental state transition implementation");
     public static final boolean RefCountIncrementOnly = parseBooleanOption("RefCountIncrementOnly", false, "Disable reference count decrements for eperimental state transition implementation");
-    public static final boolean UseNewVectorNodes = parseBooleanOption("UseNewVectorNodes", false, "temporary option");
+    public static final boolean UseNewVectorNodes = parseBooleanOption("UseNewVectorNodes", true, "temporary option");
 
     // Promises optimizations
     public static final boolean EagerEval = parseBooleanOption("EagerEval", false, "If enabled, overrides all other EagerEval switches (see EagerEvalHelper)");