Replace special IC builtins and stubs in the map's cache by codestubs.

src/builtins.cc

Index: src/builtins.cc
diff --git a/src/builtins.cc b/src/builtins.cc
index 786627da7ee9847af6a06986fde34b8305d23da5..4f373dd0f1934ae23c1483ffa7e845d50d23372c 100644
--- a/src/builtins.cc
+++ b/src/builtins.cc
@@ -1458,16 +1458,6 @@ static void Generate_LoadIC_ArrayLength(MacroAssembler* masm) {
 }
 
 
-static void Generate_LoadIC_StringLength(MacroAssembler* masm) {
-  LoadIC::GenerateStringLength(masm, false);
-}
-
-
-static void Generate_LoadIC_StringWrapperLength(MacroAssembler* masm) {
-  LoadIC::GenerateStringLength(masm, true);
-}
-
-
 static void Generate_LoadIC_FunctionPrototype(MacroAssembler* masm) {
   LoadIC::GenerateFunctionPrototype(masm);
 }