Fix spread array inside array literal

src/preparser.h

Index: src/preparser.h
diff --git a/src/preparser.h b/src/preparser.h
index 9f586469583c5cc7681c6a78c8f3d05b7b3ed260..177dc488fc9b5b404f4676a8107143544e675483 100644
--- a/src/preparser.h
+++ b/src/preparser.h
@@ -1175,6 +1175,11 @@ class PreParserFactory {
                                       int pos) {
     return PreParserExpression::Default();
   }
+  PreParserExpression NewArrayLiteral(PreParserExpressionList values,
+                                      int first_spread_index, int literal_index,
+                                      bool is_strong, int pos) {
+    return PreParserExpression::Default();
+  }
   PreParserExpression NewObjectLiteralProperty(PreParserExpression key,
                                                PreParserExpression value,
                                                ObjectLiteralProperty::Kind kind,
@@ -2388,6 +2393,7 @@ typename ParserBase<Traits>::ExpressionT ParserBase<Traits>::ParseArrayLiteral(
   int pos = peek_position();
   typename Traits::Type::ExpressionList values =
       this->NewExpressionList(4, zone_);
+  int first_spread_index = -1;
   Expect(Token::LBRACK, CHECK_OK);
   while (peek() != Token::RBRACK) {
     bool seen_spread = false;
@@ -2410,6 +2416,9 @@ typename ParserBase<Traits>::ExpressionT ParserBase<Traits>::ParseArrayLiteral(
           this->ParseAssignmentExpression(true, classifier, CHECK_OK);
       elem = factory()->NewSpread(argument, start_pos);
       seen_spread = true;
+      if (first_spread_index < 0) {
+        first_spread_index = values->length();
+      }
     } else {
       elem = this->ParseAssignmentExpression(true, classifier, CHECK_OK);
     }
@@ -2426,7 +2435,7 @@ typename ParserBase<Traits>::ExpressionT ParserBase<Traits>::ParseArrayLiteral(
   // Update the scope information before the pre-parsing bailout.
   int literal_index = function_state_->NextMaterializedLiteralIndex();
 
-  return factory()->NewArrayLiteral(values, literal_index,
+  return factory()->NewArrayLiteral(values, first_spread_index, literal_index,
                                     is_strong(language_mode()), pos);
 }