Reland "Allocation site support for monomorphic StringAdds in BinaryOps".

src/typing.cc

Index: src/typing.cc
diff --git a/src/typing.cc b/src/typing.cc
index de9f4041e7755cb915af24739d912cc94583aa7c..c692f485e63fa5b313f419872eee9272a07ad86f 100644
--- a/src/typing.cc
+++ b/src/typing.cc
@@ -629,11 +629,14 @@ void AstTyper::VisitBinaryOperation(BinaryOperation* expr) {
   // Collect type feedback.
   Handle<Type> type, left_type, right_type;
   Maybe<int> fixed_right_arg;
+  Handle<AllocationSite> allocation_site;
   oracle()->BinaryType(expr->BinaryOperationFeedbackId(),
-      &left_type, &right_type, &type, &fixed_right_arg, expr->op());
+      &left_type, &right_type, &type, &fixed_right_arg,
+      &allocation_site, expr->op());
   NarrowLowerType(expr, type);
   NarrowLowerType(expr->left(), left_type);
   NarrowLowerType(expr->right(), right_type);
+  expr->set_allocation_site(allocation_site);
   expr->set_fixed_right_arg(fixed_right_arg);
   if (expr->op() == Token::OR || expr->op() == Token::AND) {
     expr->left()->RecordToBooleanTypeFeedback(oracle());