MIPS: Support fast case for-in in Crankshaft.

src/mips/macro-assembler-mips.h

Index: src/mips/macro-assembler-mips.h
diff --git a/src/mips/macro-assembler-mips.h b/src/mips/macro-assembler-mips.h
index 56a3433b86ffe8b421f927e9bbb703e726344a98..6ae8657e1e6399114a0ebddbb62f2421d7ed8dcd 100644
--- a/src/mips/macro-assembler-mips.h
+++ b/src/mips/macro-assembler-mips.h
@@ -1353,6 +1353,10 @@ class MacroAssembler: public Assembler {
                          Register value,
                          Register scratch);
 
+  // Expects object in a0 and returns map with validated enum cache
+  // in a0.  Assumes that any other register can be used as a scratch.
+  void CheckEnumCache(Register null_value, Label* call_runtime);
+
  private:
   void CallCFunctionHelper(Register function,
                            int num_reg_arguments,