[inspector] fix positions for single expression arrow function

src/interpreter/bytecode-array-builder.cc

 // Copyright 2015 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/interpreter/bytecode-array-builder.h"
 
 #include "src/globals.h"
 #include "src/interpreter/bytecode-array-writer.h"
 #include "src/interpreter/bytecode-dead-code-optimizer.h"
 #include "src/interpreter/bytecode-label.h"
@@ skipping 33 matching lines @@
   if (FLAG_ignition_peephole) {
     pipeline_ = new (zone) BytecodePeepholeOptimizer(pipeline_);
   }
 
   if (FLAG_ignition_reo) {
     register_optimizer_ = new (zone) BytecodeRegisterOptimizer(
         zone, &register_allocator_, fixed_register_count(), parameter_count,
         pipeline_);
   }
 
-  return_position_ =
-      literal ? std::max(literal->start_position(), literal->end_position() - 1)
-              : kNoSourcePosition;
+  return_position_ = literal ? literal->return_position() : kNoSourcePosition;
 }
 
 Register BytecodeArrayBuilder::first_context_register() const {
   DCHECK_GT(context_register_count_, 0);
   return Register(local_register_count_);
 }
 
 Register BytecodeArrayBuilder::last_context_register() const {
   DCHECK_GT(context_register_count_, 0);
   return Register(local_register_count_ + context_register_count_ - 1);
@@ skipping 938 matching lines @@
     RegisterList reg_list) {
   DCHECK(RegisterListIsValid(reg_list));
   if (register_optimizer_)
     register_optimizer_->PrepareOutputRegisterList(reg_list);
   return static_cast<uint32_t>(reg_list.first_register().ToOperand());
 }
 
 }  // namespace interpreter
 }  // namespace internal
 }  // namespace v8