[turbofan] Add SimplifiedOperator::Allocate operator.

src/compiler/typer.cc

Index: src/compiler/typer.cc
diff --git a/src/compiler/typer.cc b/src/compiler/typer.cc
index 6fd609f2ab2ef6fad23189d1585ce6b7b181afcc..7f176fe1ff48eb6aadb03b7d4e9fc863c850043a 100644
--- a/src/compiler/typer.cc
+++ b/src/compiler/typer.cc
@@ -1784,6 +1784,11 @@ Bounds Typer::Visitor::TypeChangeBitToBool(Node* node) {
 }
 
 
+Bounds Typer::Visitor::TypeAllocate(Node* node) {
+  return Bounds(Type::TaggedPointer());
+}
+
+
 Bounds Typer::Visitor::TypeLoadField(Node* node) {
   return Bounds(FieldAccessOf(node->op()).type);
 }