[parser] partially revert "use-strict directives in function body affect init block"

src/expression-classifier.h

 // Copyright 2015 the V8 project authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef V8_EXPRESSION_CLASSIFIER_H
 #define V8_EXPRESSION_CLASSIFIER_H
 
 #include "src/v8.h"
 
 #include "src/messages.h"
@@ skipping 29 matching lines @@
     PatternProductions =
         (BindingPatternProduction | AssignmentPatternProduction),
     FormalParametersProductions = (DistinctFormalParametersProduction |
                                    StrictModeFormalParametersProduction |
                                    StrongModeFormalParametersProduction),
     StandardProductions = ExpressionProduction | PatternProductions,
     AllProductions = (StandardProductions | FormalParametersProductions |
                       ArrowFormalParametersProduction)
   };
 
+  enum FunctionProperties { NonSimpleParameter = 1 << 0 };
+
   ExpressionClassifier()
-      : invalid_productions_(0), duplicate_finder_(nullptr) {}
+      : invalid_productions_(0),
+        function_properties_(0),
+        duplicate_finder_(nullptr) {}
 
   explicit ExpressionClassifier(DuplicateFinder* duplicate_finder)
-      : invalid_productions_(0), duplicate_finder_(duplicate_finder) {}
+      : invalid_productions_(0),
+        function_properties_(0),
+        duplicate_finder_(duplicate_finder) {}
 
   bool is_valid(unsigned productions) const {
     return (invalid_productions_ & productions) == 0;
   }
 
   DuplicateFinder* duplicate_finder() const { return duplicate_finder_; }
 
   bool is_valid_expression() const { return is_valid(ExpressionProduction); }
 
   bool is_valid_binding_pattern() const {
@@ skipping 41 matching lines @@
   }
 
   const Error& strict_mode_formal_parameter_error() const {
     return strict_mode_formal_parameter_error_;
   }
 
   const Error& strong_mode_formal_parameter_error() const {
     return strong_mode_formal_parameter_error_;
   }
 
+  bool is_simple_parameter_list() const {
+    return !(function_properties_ & NonSimpleParameter);
+  }
+
+  void RecordNonSimpleParameter() {
+    function_properties_ |= NonSimpleParameter;
+  }
+
   void RecordExpressionError(const Scanner::Location& loc,
                              MessageTemplate::Template message,
                              const char* arg = nullptr) {
     if (!is_valid_expression()) return;
     invalid_productions_ |= ExpressionProduction;
     expression_error_.location = loc;
     expression_error_.message = message;
     expression_error_.arg = arg;
   }
 
@@ skipping 85 matching lines @@
         strict_mode_formal_parameter_error_ =
             inner.strict_mode_formal_parameter_error_;
       if (errors & StrongModeFormalParametersProduction)
         strong_mode_formal_parameter_error_ =
             inner.strong_mode_formal_parameter_error_;
     }
 
     // As an exception to the above, the result continues to be a valid arrow
     // formal parameters if the inner expression is a valid binding pattern.
     if (productions & ArrowFormalParametersProduction &&
-        is_valid_arrow_formal_parameters() &&
-        !inner.is_valid_binding_pattern()) {
-      invalid_productions_ |= ArrowFormalParametersProduction;
-      arrow_formal_parameters_error_ = inner.binding_pattern_error_;
+        is_valid_arrow_formal_parameters()) {
+      // Also copy function properties if expecting an arrow function
+      // parameter
+      function_properties_ |= inner.function_properties_;
+
+      if (!inner.is_valid_binding_pattern()) {
+        invalid_productions_ |= ArrowFormalParametersProduction;
+        arrow_formal_parameters_error_ = inner.binding_pattern_error_;
+      }
     }
   }
 
  private:
   unsigned invalid_productions_;
+  unsigned function_properties_;
   Error expression_error_;
   Error binding_pattern_error_;
   Error assignment_pattern_error_;
   Error arrow_formal_parameters_error_;
   Error duplicate_formal_parameter_error_;
   Error strict_mode_formal_parameter_error_;
   Error strong_mode_formal_parameter_error_;
   DuplicateFinder* duplicate_finder_;
 };
 }
 }  // v8::internal
 
 #endif  // V8_EXPRESSION_CLASSIFIER_H