Improve error message for duplicate parameters

src/parser.cc

Index: src/parser.cc
diff --git a/src/parser.cc b/src/parser.cc
index 1b177080bb3c0f7c50c983bd4a22f441faef33b6..a420bc1a5eb1b768285b4c1ab152c663f6eca750 100644
--- a/src/parser.cc
+++ b/src/parser.cc
@@ -2057,7 +2057,7 @@ Variable* Parser::Declare(Declaration* declaration,
         if (declaration_kind == DeclarationDescriptor::NORMAL) {
           ParserTraits::ReportMessage(MessageTemplate::kVarRedeclaration, name);
         } else {
-          ParserTraits::ReportMessage(MessageTemplate::kStrictParamDupe);
+          ParserTraits::ReportMessage(MessageTemplate::kParamDupe);
         }
         *ok = false;
         return nullptr;