Rename IsDontDelete to IsConfigurable (and invert conditions)

src/hydrogen.h

Index: src/hydrogen.h
diff --git a/src/hydrogen.h b/src/hydrogen.h
index f98f28d2f58eb3e5d91e0af881296c7e2415730c..158322ffbebf37ef584faf1d4c1cc43b936b0d7a 100644
--- a/src/hydrogen.h
+++ b/src/hydrogen.h
@@ -2510,7 +2510,7 @@ class HOptimizedGraphBuilder : public HGraphBuilder, public AstVisitor {
     bool IsAccessor() const { return lookup_.IsPropertyCallbacks(); }
     bool IsTransition() const { return lookup_.IsTransition(); }
 
-    bool IsConfigurable() const { return !lookup_.IsDontDelete(); }
+    bool IsConfigurable() const { return lookup_.IsConfigurable(); }
     bool IsReadOnly() const { return lookup_.IsReadOnly(); }
     bool IsCacheable() const { return lookup_.IsCacheable(); }