[crankshaft] Eliminate unnecessary ToNumber call

src/crankshaft/hydrogen.cc

Index: src/crankshaft/hydrogen.cc
diff --git a/src/crankshaft/hydrogen.cc b/src/crankshaft/hydrogen.cc
index a2eb0ef7eee214339e3d06639d1148ef21bd25ff..09d1158b12a370cfb488204bab4dc2168c1959eb 100644
--- a/src/crankshaft/hydrogen.cc
+++ b/src/crankshaft/hydrogen.cc
@@ -2271,7 +2271,8 @@ HValue* HGraphBuilder::BuildNumberToString(HValue* object, AstType* type) {
 }
 
 HValue* HGraphBuilder::BuildToNumber(HValue* input) {
-  if (input->type().IsTaggedNumber()) {
+  if (input->type().IsTaggedNumber() ||
+      input->representation().IsSpecialization()) {
     return input;
   }
   Callable callable = CodeFactory::ToNumber(isolate());