Remove keyed_store_calling convention and friends

src/x64/ic-x64.cc

Index: src/x64/ic-x64.cc
diff --git a/src/x64/ic-x64.cc b/src/x64/ic-x64.cc
index 9bda7583d8b0e691e36cfd24d3641b2d835bb847..73052acd1ab4ad24282f45096fdaf91c542afb80 100644
--- a/src/x64/ic-x64.cc
+++ b/src/x64/ic-x64.cc
@@ -1016,21 +1016,6 @@ const Register StoreIC::NameRegister() { return rcx; }
 const Register StoreIC::ValueRegister() { return rax; }
 
 
-const Register KeyedStoreIC::ReceiverRegister() {
-  return StoreIC::ReceiverRegister();
-}
-
-
-const Register KeyedStoreIC::NameRegister() {
-  return StoreIC::NameRegister();
-}
-
-
-const Register KeyedStoreIC::ValueRegister() {
-  return StoreIC::ValueRegister();
-}
-
-
 const Register KeyedStoreIC::MapRegister() {
   return rbx;
 }