Use Unique<Map> in HTransitionElementsKind.

src/mips/lithium-mips.h

 // Copyright 2012 the V8 project authors. All rights reserved.
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions are
 // met:
 //
 //     * Redistributions of source code must retain the above copyright
 //       notice, this list of conditions and the following disclaimer.
 //     * Redistributions in binary form must reproduce the above
 //       copyright notice, this list of conditions and the following
 //       disclaimer in the documentation and/or other materials provided
@@ skipping 2232 matching lines @@
 
   LOperand* object() { return inputs_[0]; }
   LOperand* new_map_temp() { return temps_[0]; }
 
   DECLARE_CONCRETE_INSTRUCTION(TransitionElementsKind,
                                "transition-elements-kind")
   DECLARE_HYDROGEN_ACCESSOR(TransitionElementsKind)
 
   virtual void PrintDataTo(StringStream* stream) V8_OVERRIDE;
 
-  Handle<Map> original_map() { return hydrogen()->original_map(); }
-  Handle<Map> transitioned_map() { return hydrogen()->transitioned_map(); }
+  Handle<Map> original_map() { return hydrogen()->original_map().handle(); }
+  Handle<Map> transitioned_map() {
+    return hydrogen()->transitioned_map().handle();
+  }
   ElementsKind from_kind() { return hydrogen()->from_kind(); }
   ElementsKind to_kind() { return hydrogen()->to_kind(); }
 };
 
 
 class LTrapAllocationMemento V8_FINAL : public LTemplateInstruction<0, 1, 1> {
  public:
   LTrapAllocationMemento(LOperand* object,
                          LOperand* temp) {
     inputs_[0] = object;
@@ skipping 502 matching lines @@
 
   DISALLOW_COPY_AND_ASSIGN(LChunkBuilder);
 };
 
 #undef DECLARE_HYDROGEN_ACCESSOR
 #undef DECLARE_CONCRETE_INSTRUCTION
 
 } }  // namespace v8::internal
 
 #endif  // V8_MIPS_LITHIUM_MIPS_H_