[turbofan] Introduce a dedicated CheckBounds operator.

src/compiler/typer.cc

Index: src/compiler/typer.cc
diff --git a/src/compiler/typer.cc b/src/compiler/typer.cc
index 165779bad5285375c97847c2b24bc91d7b439b01..84404a143dee006812cbd60c0a01d321763474fb 100644
--- a/src/compiler/typer.cc
+++ b/src/compiler/typer.cc
@@ -1945,6 +1945,11 @@ Type* Typer::Visitor::TypeChangeBitToTagged(Node* node) {
   return ChangeRepresentation(arg, Type::TaggedPointer(), zone());
 }
 
+Type* Typer::Visitor::TypeCheckBounds(Node* node) {
+  // TODO(bmeurer): We could do better here based on the limit.
+  return Type::Unsigned31();
+}
+
 Type* Typer::Visitor::TypeCheckedUint32ToInt32(Node* node) {
   return Type::Signed32();
 }