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

src/ic/mips64/handler-compiler-mips64.cc

Index: src/ic/mips64/handler-compiler-mips64.cc
diff --git a/src/ic/mips64/handler-compiler-mips64.cc b/src/ic/mips64/handler-compiler-mips64.cc
index b5e7d42e57c6e377b1ac951580992d4d16cc38ab..8d6dc34615f3d501e1d57e684d454f9ea467c351 100644
--- a/src/ic/mips64/handler-compiler-mips64.cc
+++ b/src/ic/mips64/handler-compiler-mips64.cc
@@ -737,7 +737,7 @@ Handle<Code> NamedStoreHandlerCompiler::CompileStoreCallback(
   __ TailCallRuntime(Runtime::kStoreCallbackProperty);
 
   // Return the generated code.
-  return GetCode(kind(), Code::FAST, name);
+  return GetCode(kind(), name);
 }
 
 
@@ -778,7 +778,7 @@ Handle<Code> NamedLoadHandlerCompiler::CompileLoadGlobal(
   FrontendFooter(name, &miss);
 
   // Return the generated code.
-  return GetCode(kind(), Code::NORMAL, name);
+  return GetCode(kind(), name);
 }