[mips] Fix using signaling NaN for holes in fixed double arrays.

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 ceb40fa293e7e1ad2df60f10555e8383d4ea1817..e4d88b65f1b461886f9245bacfaa2db6b0e10483 100644
--- a/src/mips/macro-assembler-mips.h
+++ b/src/mips/macro-assembler-mips.h
@@ -1237,6 +1237,9 @@ class MacroAssembler: public Assembler {
                        Handle<WeakCell> cell, Handle<Code> success,
                        SmiCheckType smi_check_type);
 
+  // If the value is a NaN, canonicalize the value else, do nothing.
+  void FPUCanonicalizeNaN(const DoubleRegister dst, const DoubleRegister src);
+
   // Get value of the weak cell.
   void GetWeakValue(Register value, Handle<WeakCell> cell);