X87: [crankshaft] Refactor kAllowUndefinedAsNaN to kTruncatingToNumber.

src/crankshaft/x87/lithium-codegen-x87.cc

Index: src/crankshaft/x87/lithium-codegen-x87.cc
diff --git a/src/crankshaft/x87/lithium-codegen-x87.cc b/src/crankshaft/x87/lithium-codegen-x87.cc
index 28d0a65165f1a67adfe90ca61be8f60e3921d65d..0edaaa4ce11d26952dfa7e3059a60ff589544e18 100644
--- a/src/crankshaft/x87/lithium-codegen-x87.cc
+++ b/src/crankshaft/x87/lithium-codegen-x87.cc
@@ -4596,8 +4596,7 @@ void LCodeGen::DoSmiUntag(LSmiUntag* instr) {
 void LCodeGen::EmitNumberUntagDNoSSE2(LNumberUntagD* instr, Register input_reg,
                                       Register temp_reg, X87Register res_reg,
                                       NumberUntagDMode mode) {
-  bool can_convert_undefined_to_nan =
-      instr->hydrogen()->can_convert_undefined_to_nan();
+  bool can_convert_undefined_to_nan = instr->truncating();
   bool deoptimize_on_minus_zero = instr->hydrogen()->deoptimize_on_minus_zero();
 
   Label load_smi, done;