Use Unique<Map> in CompareMap.

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 1268 matching lines @@
     inputs_[0] = value;
     temps_[0] = temp;
   }
 
   LOperand* value() { return inputs_[0]; }
   LOperand* temp() { return temps_[0]; }
 
   DECLARE_CONCRETE_INSTRUCTION(CmpMapAndBranch, "cmp-map-and-branch")
   DECLARE_HYDROGEN_ACCESSOR(CompareMap)
 
-  Handle<Map> map() const { return hydrogen()->map(); }
+  Handle<Map> map() const { return hydrogen()->map().handle(); }
 };
 
 
 class LMapEnumLength V8_FINAL : public LTemplateInstruction<1, 1, 0> {
  public:
   explicit LMapEnumLength(LOperand* value) {
     inputs_[0] = value;
   }
 
   LOperand* value() { return inputs_[0]; }
@@ skipping 1457 matching lines @@
 
   DISALLOW_COPY_AND_ASSIGN(LChunkBuilder);
 };
 
 #undef DECLARE_HYDROGEN_ACCESSOR
 #undef DECLARE_CONCRETE_INSTRUCTION
 
 } }  // namespace v8::internal
 
 #endif  // V8_MIPS_LITHIUM_MIPS_H_