[inspector] fix positions for single expression arrow function

src/parsing/parser-base.h

Index: src/parsing/parser-base.h
diff --git a/src/parsing/parser-base.h b/src/parsing/parser-base.h
index c349cdd094855420aa2c29ff985eb2777650ce27..02df5cf392f01b432d8f972849d53eddb47d6917 100644
--- a/src/parsing/parser-base.h
+++ b/src/parsing/parser-base.h
@@ -2276,7 +2276,7 @@ ParserBase<Impl>::ParseClassFieldForInitializer(bool has_initializer,
       initializer_state.expected_property_count(), 0, 0,
       FunctionLiteral::kNoDuplicateParameters,
       FunctionLiteral::kAnonymousExpression, default_eager_compile_hint_,
-      initializer_scope->start_position());
+      initializer_scope->start_position(), true);
   function_literal->set_is_class_field_initializer(true);
   return function_literal;
 }
@@ -3910,6 +3910,7 @@ ParserBase<Impl>::ParseArrowFunctionLiteral(
   bool is_lazy_top_level_function =
       can_preparse && impl()->AllowsLazyParsingWithoutUnresolvedVariables();
   bool should_be_used_once_hint = false;
+  bool has_braces = true;
   {
     FunctionState function_state(&function_state_, &scope_state_,
                                  formal_parameters.scope);
@@ -3972,6 +3973,7 @@ ParserBase<Impl>::ParseArrowFunctionLiteral(
       }
     } else {
       // Single-expression body
+      has_braces = false;
       int pos = position();
       DCHECK(ReturnExprContext::kInsideValidBlock ==
              function_state_->return_expr_context());
@@ -3989,7 +3991,9 @@ ParserBase<Impl>::ParseArrowFunctionLiteral(
       } else {
         ExpressionT expression = ParseAssignmentExpression(accept_IN, CHECK_OK);
         impl()->RewriteNonPattern(CHECK_OK);
-        body->Add(factory()->NewReturnStatement(expression, pos), zone());
+        body->Add(
+            factory()->NewReturnStatement(expression, expression->position()),
+            zone());
         if (allow_tailcalls() && !is_sloppy(language_mode())) {
           // ES6 14.6.1 Static Semantics: IsInTailPosition
           impl()->MarkTailPosition(expression);
@@ -4032,7 +4036,7 @@ ParserBase<Impl>::ParseArrowFunctionLiteral(
       formal_parameters.num_parameters(), formal_parameters.function_length,
       FunctionLiteral::kNoDuplicateParameters,
       FunctionLiteral::kAnonymousExpression, eager_compile_hint,
-      formal_parameters.scope->start_position());
+      formal_parameters.scope->start_position(), has_braces);
 
   function_literal->set_function_token_position(
       formal_parameters.scope->start_position());