MIPS: Add negative lookups to polymorphic loads in Crankshaft.

src/mips/lithium-codegen-mips.h

Index: src/mips/lithium-codegen-mips.h
diff --git a/src/mips/lithium-codegen-mips.h b/src/mips/lithium-codegen-mips.h
index 61a15a3ee8536a0825e764729d604d7c14677061..32a696bc30d0af5f8ce093fba763cc19f3233c5f 100644
--- a/src/mips/lithium-codegen-mips.h
+++ b/src/mips/lithium-codegen-mips.h
@@ -334,7 +334,8 @@ class LCodeGen BASE_EMBEDDED {
   void EmitLoadFieldOrConstantFunction(Register result,
                                        Register object,
                                        Handle<Map> type,
-                                       Handle<String> name);
+                                       Handle<String> name,
+                                       LEnvironment* env);
 
   // Emits optimized code to deep-copy the contents of statically known
   // object graphs (e.g. object literal boilerplate).