Fix A64 build: unwrap HSourcePosition into int before recording.

src/a64/lithium-a64.cc

 // Copyright 2013 the V8 project authors. All rights reserved.
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions are
 // met:
 //
 //     * Redistributions of source code must retain the above copyright
 //       notice, this list of conditions and the following disclaimer.
 //     * Redistributions in binary form must reproduce the above
 //       copyright notice, this list of conditions and the following
 //       disclaimer in the documentation and/or other materials provided
@@ skipping 653 matching lines @@
     block->set_last_instruction_index(end);
   }
   block->set_argument_count(argument_count_);
   current_block_ = NULL;
 }
 
 
 void LChunkBuilder::VisitInstruction(HInstruction* current) {
   HInstruction* old_current = current_instruction_;
   current_instruction_ = current;
-  if (current->has_position()) position_ = current->position();
 
   LInstruction* instr = NULL;
   if (current->CanReplaceWithDummyUses()) {
     if (current->OperandCount() == 0) {
       instr = DefineAsRegister(new(zone()) LDummy());
     } else {
       ASSERT(!current->OperandAt(0)->IsControlInstruction());
       instr = DefineAsRegister(new(zone())
           LDummyUse(UseAny(current->OperandAt(0))));
     }
@@ skipping 1758 matching lines @@
 
 LInstruction* LChunkBuilder::DoWrapReceiver(HWrapReceiver* instr) {
   LOperand* receiver = UseRegister(instr->receiver());
   LOperand* function = UseRegister(instr->function());
   LWrapReceiver* result = new(zone()) LWrapReceiver(receiver, function);
   return AssignEnvironment(DefineAsRegister(result));
 }
 
 
 } }  // namespace v8::internal