[regexp] Remove unused code

src/x64/interface-descriptors-x64.cc

Index: src/x64/interface-descriptors-x64.cc
diff --git a/src/x64/interface-descriptors-x64.cc b/src/x64/interface-descriptors-x64.cc
index 5ca6deb121e0f92ac74b4c8070f4563fa6c51090..24fc92852a9054f404b6c6d332b6a01d0b1c6087 100644
--- a/src/x64/interface-descriptors-x64.cc
+++ b/src/x64/interface-descriptors-x64.cc
@@ -202,13 +202,6 @@ void ConstructTrampolineDescriptor::InitializePlatformSpecific(
 }
 
 
-void RegExpConstructResultDescriptor::InitializePlatformSpecific(
-    CallInterfaceDescriptorData* data) {
-  Register registers[] = {rcx, rbx, rax};
-  data->InitializePlatformSpecific(arraysize(registers), registers);
-}
-
-
 void TransitionElementsKindDescriptor::InitializePlatformSpecific(
     CallInterfaceDescriptorData* data) {
   Register registers[] = {rax, rbx};