[arm] Turn off the default NaN mode on arm.

src/arm/macro-assembler-arm.h

Index: src/arm/macro-assembler-arm.h
diff --git a/src/arm/macro-assembler-arm.h b/src/arm/macro-assembler-arm.h
index d55d33cb01694a4be07bd8826a00591f7934483d..1f2f95811c3a3ac8973bb63177e5c2c551d19431 100644
--- a/src/arm/macro-assembler-arm.h
+++ b/src/arm/macro-assembler-arm.h
@@ -489,15 +489,6 @@ class MacroAssembler: public Assembler {
             const MemOperand& dst,
             Condition cond = al);
 
-  // Ensure that FPSCR contains values needed by JavaScript.
-  // We need the NaNModeControlBit to be sure that operations like
-  // vadd and vsub generate the Canonical NaN (if a NaN must be generated).
-  // In VFP3 it will be always the Canonical NaN.
-  // In VFP2 it will be either the Canonical NaN or the negative version
-  // of the Canonical NaN. It doesn't matter if we have two values. The aim
-  // is to be sure to never generate the hole NaN.
-  void VFPEnsureFPSCRState(Register scratch);
-
   // If the value is a NaN, canonicalize the value else, do nothing.
   void VFPCanonicalizeNaN(const DwVfpRegister dst,
                           const DwVfpRegister src,