[turbofan] add configuration parameters for register allocator

src/compiler/x64/linkage-x64.cc

 // Copyright 2014 the V8 project authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "src/v8.h"
 
 #include "src/assembler.h"
 #include "src/code-stubs.h"
 #include "src/compiler/linkage.h"
 #include "src/compiler/linkage-impl.h"
@@ skipping 45 matching lines @@
 
 CallDescriptor* Linkage::GetRuntimeCallDescriptor(
     Runtime::FunctionId function, int parameter_count,
     Operator::Properties properties, Zone* zone) {
   return LH::GetRuntimeCallDescriptor(zone, function, parameter_count,
                                       properties);
 }
 
 
 CallDescriptor* Linkage::GetStubCallDescriptor(
-    CallInterfaceDescriptor descriptor, int stack_parameter_count,
+    const CallInterfaceDescriptor& descriptor, int stack_parameter_count,
     CallDescriptor::Flags flags, Zone* zone) {
   return LH::GetStubCallDescriptor(zone, descriptor, stack_parameter_count,
                                    flags);
 }
 
 
 CallDescriptor* Linkage::GetSimplifiedCDescriptor(Zone* zone,
                                                   MachineSignature* sig) {
   return LH::GetSimplifiedCDescriptor(zone, sig);
 }
 
 }  // namespace compiler
 }  // namespace internal
 }  // namespace v8