[strong] Class constructor bodies cannot contain "use strong" directive

src/messages.h

 // Copyright 2006-2008 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.
 
 // The infrastructure used for (localized) message reporting in V8.
 //
 // Note: there's a big unresolved issue about ownership of the data
 // structures used by this framework.
 
 #ifndef V8_MESSAGES_H_
@@ skipping 316 matching lines @@
     "supported outside strict mode")                                           \
   T(StrictDelete, "Delete of an unqualified identifier in strict mode.")       \
   T(StrictEvalArguments, "Unexpected eval or arguments in strict mode")        \
   T(StrictFunction,                                                            \
     "In strict mode code, functions can only be declared at top level or "     \
     "immediately within another function.")                                    \
   T(StrictOctalLiteral, "Octal literals are not allowed in strict mode.")      \
   T(StrictWith, "Strict mode code may not include a with statement")           \
   T(StrongArguments,                                                           \
     "In strong mode, 'arguments' is deprecated, use '...args' instead")        \
+  T(StrongConstructorDirective,                                                \
+    "\"use strong\" directive is disallowed in class constructor body")        \
   T(StrongConstructorReturnMisplaced,                                          \
     "In strong mode, returning from a constructor before its super "           \
     "constructor invocation or all assignments to 'this' is deprecated")       \
   T(StrongConstructorReturnValue,                                              \
     "In strong mode, returning a value from a constructor is deprecated")      \
   T(StrongConstructorSuper,                                                    \
     "In strong mode, 'super' can only be used to invoke the super "            \
     "constructor, and cannot be nested inside another statement or "           \
     "expression")                                                              \
   T(StrongConstructorThis,                                                     \
@@ skipping 135 matching lines @@
 
   static MUST_USE_RESULT MaybeHandle<String> GetStringifiedProperty(
       Isolate* isolate, LookupIterator* property_lookup,
       Handle<String> default_value);
 
   List<Handle<JSObject> > visited_;
 };
 } }  // namespace v8::internal
 
 #endif  // V8_MESSAGES_H_