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

src/arm64/code-stubs-arm64.cc

Index: src/arm64/code-stubs-arm64.cc
diff --git a/src/arm64/code-stubs-arm64.cc b/src/arm64/code-stubs-arm64.cc
index b72684a36930279c5727dfe6cb25794738b9d99b..f0265c73cee09edb9d889b803cf853f73edcc0fd 100644
--- a/src/arm64/code-stubs-arm64.cc
+++ b/src/arm64/code-stubs-arm64.cc
@@ -3827,8 +3827,8 @@ void LoadICStub::GenerateImpl(MacroAssembler* masm, bool in_frame) {
 
   __ Bind(&not_array);
   __ JumpIfNotRoot(feedback, Heap::kmegamorphic_symbolRootIndex, &miss);
-  Code::Flags code_flags = Code::RemoveTypeAndHolderFromFlags(
-      Code::ComputeHandlerFlags(Code::LOAD_IC));
+  Code::Flags code_flags =
+      Code::RemoveHolderFromFlags(Code::ComputeHandlerFlags(Code::LOAD_IC));
   masm->isolate()->stub_cache()->GenerateProbe(masm, Code::LOAD_IC, code_flags,
                                                receiver, name, feedback,
                                                receiver_map, scratch1, x7);
@@ -3963,8 +3963,8 @@ void VectorStoreICStub::GenerateImpl(MacroAssembler* masm, bool in_frame) {
 
   __ Bind(&not_array);
   __ JumpIfNotRoot(feedback, Heap::kmegamorphic_symbolRootIndex, &miss);
-  Code::Flags code_flags = Code::RemoveTypeAndHolderFromFlags(
-      Code::ComputeHandlerFlags(Code::STORE_IC));
+  Code::Flags code_flags =
+      Code::RemoveHolderFromFlags(Code::ComputeHandlerFlags(Code::STORE_IC));
   masm->isolate()->stub_cache()->GenerateProbe(masm, Code::STORE_IC, code_flags,
                                                receiver, key, feedback,
                                                receiver_map, scratch1, x8);