Add strong mode.

src/hydrogen-instructions.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_INSTRUCTIONS_H_
 #define V8_HYDROGEN_INSTRUCTIONS_H_
 
 #include <cstring>
 #include <iosfwd>
 
@@ skipping 7596 matching lines @@
     SetOperandAt(0, context);
     set_representation(Representation::Tagged());
     SetChangesFlag(kNewSpacePromotion);
   }
 
   bool IsDeletable() const OVERRIDE { return true; }
 
   class FunctionKindField : public BitField<FunctionKind, 0, 4> {};
   class PretenureField : public BitField<bool, 5, 1> {};
   class HasNoLiteralsField : public BitField<bool, 6, 1> {};
-  STATIC_ASSERT(LANGUAGE_END == 2);
-  class LanguageModeField : public BitField<LanguageMode, 7, 1> {};
+  STATIC_ASSERT(LANGUAGE_END == 3);
+  class LanguageModeField : public BitField<LanguageMode, 7, 2> {};
 
   Handle<SharedFunctionInfo> shared_info_;
   uint32_t bit_field_;
 };
 
 
 class HTypeof FINAL : public HTemplateInstruction<2> {
  public:
   DECLARE_INSTRUCTION_WITH_CONTEXT_FACTORY_P1(HTypeof, HValue*);
 
@@ skipping 366 matching lines @@
 };
 
 
 
 #undef DECLARE_INSTRUCTION
 #undef DECLARE_CONCRETE_INSTRUCTION
 
 } }  // namespace v8::internal
 
 #endif  // V8_HYDROGEN_INSTRUCTIONS_H_