[inspector] fix positions for single expression arrow function

src/ast/ast.h

 // Copyright 2012 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.
 
 #ifndef V8_AST_AST_H_
 #define V8_AST_AST_H_
 
 #include "src/ast/ast-types.h"
 #include "src/ast/ast-value-factory.h"
 #include "src/ast/modules.h"
@@ skipping 2690 matching lines @@
         RequiresClassFieldInit::update(bit_field_, requires_class_field_init);
   }
   bool is_class_field_initializer() {
     return IsClassFieldInitializer::decode(bit_field_);
   }
   void set_is_class_field_initializer(bool is_class_field_initializer) {
     bit_field_ =
         IsClassFieldInitializer::update(bit_field_, is_class_field_initializer);
   }
 
+  bool HasSingleReturnBody() {
+    return body_->length() == 1 &&

[Yang, 2016/11/08 12:23:33]

I think adding another flag to FunctionLiteral makes a lot more sense than try
to reverse engineer here.

[kozy, 2016/11/08 16:28:45]

Done.

+           body_->at(0)->node_type() == AstNode::kReturnStatement;
+  }
+
  private:
   friend class AstNodeFactory;
 
   FunctionLiteral(Zone* zone, const AstString* name,
                   AstValueFactory* ast_value_factory, DeclarationScope* scope,
                   ZoneList<Statement*>* body, int materialized_literal_count,
                   int expected_property_count, int parameter_count,
                   int function_length, FunctionType function_type,
                   ParameterFlag has_duplicate_parameters,
                   EagerCompileHint eager_compile_hint, int position,
@@ skipping 876 matching lines @@
                                     : NULL;                                   \
   }
 AST_NODE_LIST(DECLARE_NODE_FUNCTIONS)
 #undef DECLARE_NODE_FUNCTIONS
 
 
 }  // namespace internal
 }  // namespace v8
 
 #endif  // V8_AST_AST_H_