[strong] Disallow implicit conversions for add

src/hydrogen.h

 // Copyright 2012 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_HYDROGEN_H_
 #define V8_HYDROGEN_H_
 
 #include "src/v8.h"
 
 #include "src/accessors.h"
@@ skipping 1419 matching lines @@
                         HValue** shift_amount);
 
   HValue* BuildBinaryOperation(Token::Value op,
                                HValue* left,
                                HValue* right,
                                Type* left_type,
                                Type* right_type,
                                Type* result_type,
                                Maybe<int> fixed_right_arg,
                                HAllocationMode allocation_mode,
-                               LanguageMode language_mode = SLOPPY);
+                               LanguageMode language_mode);
 
   HLoadNamedField* AddLoadFixedArrayLength(HValue *object,
                                            HValue *dependency = NULL);
 
   HLoadNamedField* AddLoadArrayLength(HValue *object,
                                       ElementsKind kind,
                                       HValue *dependency = NULL);
 
   HValue* AddLoadJSBuiltin(Builtins::JavaScript builtin);
 
@@ skipping 1597 matching lines @@
   }
 
  private:
   HGraphBuilder* builder_;
 };
 
 
 } }  // namespace v8::internal
 
 #endif  // V8_HYDROGEN_H_