[turbofan] Unify Math.floor / Math.ceil optimization.

src/compiler/typer.cc

Index: src/compiler/typer.cc
diff --git a/src/compiler/typer.cc b/src/compiler/typer.cc
index 0a7d55d82e76d8434fecf657418d78e1c09517d2..9934741767140ae4fff9b878d5385edcb7c9c736 100644
--- a/src/compiler/typer.cc
+++ b/src/compiler/typer.cc
@@ -1510,6 +1510,7 @@ Bounds Typer::Visitor::TypeJSCallRuntime(Node* node) {
     case Runtime::kInlineDoubleHi:
       return Bounds(Type::None(zone()), Type::Signed32());
     case Runtime::kInlineConstructDouble:
+    case Runtime::kInlineMathFloor:
       return Bounds(Type::None(zone()), Type::Number());
     default:
       break;
@@ -2085,13 +2086,7 @@ Bounds Typer::Visitor::TypeFloat64LessThanOrEqual(Node* node) {
 }
 
 
-Bounds Typer::Visitor::TypeFloat64Floor(Node* node) {
-  // TODO(sigurds): We could have a tighter bound here.
-  return Bounds(Type::Number());
-}
-
-
-Bounds Typer::Visitor::TypeFloat64Ceil(Node* node) {
+Bounds Typer::Visitor::TypeFloat64RoundDown(Node* node) {
   // TODO(sigurds): We could have a tighter bound here.
   return Bounds(Type::Number());
 }