Use ExpressionClassifier to identify valid arrow function formals

src/parser.cc

Index: src/parser.cc
diff --git a/src/parser.cc b/src/parser.cc
index 26771e4e347830c81c13377cbd24c7d1d5897213..6422a94c02882da5e7d8ba816f5bc454937deb57 100644
--- a/src/parser.cc
+++ b/src/parser.cc
@@ -1150,10 +1150,8 @@ FunctionLiteral* Parser::ParseLazy(Isolate* isolate, ParseInfo* info,
       }
 
       if (ok) {
-        ExpressionClassifier classifier;
-        Expression* expression = ParseArrowFunctionLiteral(
-            scope, error_locs, has_rest, &classifier, &ok);
-        ValidateExpression(&classifier, &ok);
+        Expression* expression =
+            ParseArrowFunctionLiteral(scope, error_locs, has_rest, &ok);
         if (ok) {
           // Scanning must end at the same position that was recorded
           // previously. If not, parsing has been interrupted due to a stack