[parser] Delete misplaced const.

src/parsing/preparser.h

Index: src/parsing/preparser.h
diff --git a/src/parsing/preparser.h b/src/parsing/preparser.h
index 2a8c349fb35aa9b761999974922fc3aa00970269..75afe09bb77c42af90c0725402561b9b4c4ac7d0 100644
--- a/src/parsing/preparser.h
+++ b/src/parsing/preparser.h
@@ -892,7 +892,7 @@ class PreParser : public ParserBase<PreParser> {
         track_unresolved_variables_(false),
         pending_error_handler_(pending_error_handler) {}
 
-  static bool const IsPreParser() { return true; }
+  static bool IsPreParser() { return true; }
 
   PreParserLogger* logger() { return &log_; }