Add Float64Round operator.

src/compiler/typer.cc

Index: src/compiler/typer.cc
diff --git a/src/compiler/typer.cc b/src/compiler/typer.cc
index ae7a464883672344013edf7335b53358a835c30c..e18c43083e895695a2c8398d831280eb2a7bfd1a 100644
--- a/src/compiler/typer.cc
+++ b/src/compiler/typer.cc
@@ -1554,6 +1554,30 @@ 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) {
+  // TODO(sigurds): We could have a tighter bound here.
+  return Bounds(Type::Number());
+}
+
+
+Bounds Typer::Visitor::TypeFloat64RoundTruncate(Node* node) {
+  // TODO(sigurds): We could have a tighter bound here.
+  return Bounds(Type::Number());
+}
+
+
+Bounds Typer::Visitor::TypeFloat64RoundTiesAway(Node* node) {
+  // TODO(sigurds): We could have a tighter bound here.
+  return Bounds(Type::Number());
+}
+
+
 Bounds Typer::Visitor::TypeLoadStackPointer(Node* node) {
   return Bounds(Type::Internal());
 }