Revert "Create a RegisterSpec class inside of the IC that provides:"

src/arm64/stub-cache-arm64.cc

Index: src/arm64/stub-cache-arm64.cc
diff --git a/src/arm64/stub-cache-arm64.cc b/src/arm64/stub-cache-arm64.cc
index 0088a4d247340dede3e4f183108e78e68e5f7c83..9311645bb1e813e7b42b0e54c1c9c86a6ef76913 100644
--- a/src/arm64/stub-cache-arm64.cc
+++ b/src/arm64/stub-cache-arm64.cc
@@ -1245,18 +1245,14 @@ Handle<Code> LoadStubCompiler::CompileLoadNonexistent(Handle<HeapType> type,
 
 Register* LoadStubCompiler::registers() {
   // receiver, name, scratch1, scratch2, scratch3, scratch4.
-  Register receiver = LoadIC::kReceiverRegister;
-  Register name = LoadIC::kNameRegister;
-  static Register registers[] = { receiver, name, x3, x1, x4, x5 };
+  static Register registers[] = { x0, x2, x3, x1, x4, x5 };
   return registers;
 }
 
 
 Register* KeyedLoadStubCompiler::registers() {
-  // receiver, name, scratch1, scratch2, scratch3, scratch4.
-  Register receiver = KeyedLoadIC::kReceiverRegister;
-  Register name = KeyedLoadIC::kNameRegister;
-  static Register registers[] = { receiver, name, x2, x3, x4, x5 };
+  // receiver, name/key, scratch1, scratch2, scratch3, scratch4.
+  static Register registers[] = { x1, x0, x2, x3, x4, x5 };
   return registers;
 }