[turbofan] Added the optional Float64RoundTiesEven operator to turbofan.

src/compiler/arm/code-generator-arm.cc

Index: src/compiler/arm/code-generator-arm.cc
diff --git a/src/compiler/arm/code-generator-arm.cc b/src/compiler/arm/code-generator-arm.cc
index 7b848ac812b5bd54ae83a21ec4be87ce9b5a9597..76e9050b441c423ab3476d6fe961f4e6580d18c2 100644
--- a/src/compiler/arm/code-generator-arm.cc
+++ b/src/compiler/arm/code-generator-arm.cc
@@ -779,6 +779,9 @@ void CodeGenerator::AssembleArchInstruction(Instruction* instr) {
     case kArmVrintaF64:
       __ vrinta(i.OutputFloat64Register(), i.InputFloat64Register(0));
       break;
+    case kArmVrintnF64:
+      __ vrintn(i.OutputFloat64Register(), i.InputFloat64Register(0));
+      break;
     case kArmVcvtF32F64: {
       __ vcvt_f32_f64(i.OutputFloat32Register(), i.InputFloat64Register(0));
       DCHECK_EQ(LeaveCC, i.OutputSBit());