Ensure slow properties for simple {__proto__:null} literals.

src/interpreter/bytecode-flags.h

Index: src/interpreter/bytecode-flags.h
diff --git a/src/interpreter/bytecode-flags.h b/src/interpreter/bytecode-flags.h
index 98459e7feda02b2d01511e8d53b885ca12866078..c868255ca5996e8d4d334b5edfc6756649252ade 100644
--- a/src/interpreter/bytecode-flags.h
+++ b/src/interpreter/bytecode-flags.h
@@ -18,7 +18,7 @@ namespace interpreter {
 
 class CreateArrayLiteralFlags {
  public:
-  class FlagsBits : public BitField8<int, 0, 3> {};
+  class FlagsBits : public BitField8<int, 0, 4> {};
   class FastShallowCloneBit : public BitField8<bool, FlagsBits::kNext, 1> {};
 
   static uint8_t Encode(bool use_fast_shallow_clone, int runtime_flags);
@@ -29,7 +29,7 @@ class CreateArrayLiteralFlags {
 
 class CreateObjectLiteralFlags {
  public:
-  class FlagsBits : public BitField8<int, 0, 3> {};
+  class FlagsBits : public BitField8<int, 0, 4> {};
   class FastClonePropertiesCountBits
       : public BitField8<int, FlagsBits::kNext, 3> {};