Use a dictionary-mode code cache on the map rather than a dual system.

src/ic/ia32/ic-ia32.cc

Index: src/ic/ia32/ic-ia32.cc
diff --git a/src/ic/ia32/ic-ia32.cc b/src/ic/ia32/ic-ia32.cc
index e66716f6cb02a96ae38828f1a440540b25ef8e7d..c09d90204dc935abafe83fb56c28ed951ae1cd49 100644
--- a/src/ic/ia32/ic-ia32.cc
+++ b/src/ic/ia32/ic-ia32.cc
@@ -336,8 +336,8 @@ void KeyedLoadIC::GenerateMegamorphic(MacroAssembler* masm) {
   __ push(Immediate(Smi::FromInt(slot)));
   __ push(Immediate(dummy_vector));
 
-  Code::Flags flags = Code::RemoveTypeAndHolderFromFlags(
-      Code::ComputeHandlerFlags(Code::LOAD_IC));
+  Code::Flags flags =
+      Code::RemoveHolderFromFlags(Code::ComputeHandlerFlags(Code::LOAD_IC));
   masm->isolate()->stub_cache()->GenerateProbe(masm, Code::KEYED_LOAD_IC, flags,
                                                receiver, key, ebx, edi);
 
@@ -563,8 +563,8 @@ void KeyedStoreIC::GenerateMegamorphic(MacroAssembler* masm,
   __ push(Immediate(Smi::FromInt(slot)));
   __ push(Immediate(dummy_vector));
 
-  Code::Flags flags = Code::RemoveTypeAndHolderFromFlags(
-      Code::ComputeHandlerFlags(Code::STORE_IC));
+  Code::Flags flags =
+      Code::RemoveHolderFromFlags(Code::ComputeHandlerFlags(Code::STORE_IC));
   masm->isolate()->stub_cache()->GenerateProbe(masm, Code::STORE_IC, flags,
                                                receiver, key, edi, no_reg);