Use IC register definitions in platform files.

src/x64/code-stubs-x64.cc

Index: src/x64/code-stubs-x64.cc
diff --git a/src/x64/code-stubs-x64.cc b/src/x64/code-stubs-x64.cc
index d1c08b64a32417f13749f44a060e12e641e0462d..7bcf129b5163e2b92e19b64e6a0448d1cc28d8d5 100644
--- a/src/x64/code-stubs-x64.cc
+++ b/src/x64/code-stubs-x64.cc
@@ -89,34 +89,6 @@ void RegExpConstructResultStub::InitializeInterfaceDescriptor(
 }
 
 
-void LoadFieldStub::InitializeInterfaceDescriptor(
-    CodeStubInterfaceDescriptor* descriptor) {
-  Register registers[] = { rax };
-  descriptor->Initialize(ARRAY_SIZE(registers), registers);
-}
-
-
-void KeyedLoadFieldStub::InitializeInterfaceDescriptor(
-    CodeStubInterfaceDescriptor* descriptor) {
-  Register registers[] = { rdx };
-  descriptor->Initialize(ARRAY_SIZE(registers), registers);
-}
-
-
-void StringLengthStub::InitializeInterfaceDescriptor(
-    CodeStubInterfaceDescriptor* descriptor) {
-  Register registers[] = { rax, rcx };
-  descriptor->Initialize(ARRAY_SIZE(registers), registers);
-}
-
-
-void KeyedStringLengthStub::InitializeInterfaceDescriptor(
-    CodeStubInterfaceDescriptor* descriptor) {
-  Register registers[] = { rdx, rax };
-  descriptor->Initialize(ARRAY_SIZE(registers), registers);
-}
-
-
 void KeyedStoreFastElementStub::InitializeInterfaceDescriptor(
     CodeStubInterfaceDescriptor* descriptor) {
   Register registers[] = { rdx, rcx, rax };