Adding visitors to regurgitate expression types or reset them.

src/typing-reset.h

+// Copyright 2015 the V8 project authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#ifndef V8_TYPING_RESET_H_
+#define V8_TYPING_RESET_H_
+
+#include "src/ast-expression-visitor.h"
+
+namespace v8 {
+namespace internal {
+
+// A Visitor over a CompilationInfo's AST that resets
+// typing bounds back to their default.
+
+class TypingReseter : public AstExpressionVisitor {
+ public:
+  static void Run(CompilationInfo* info);
+
+ protected:
+  void VisitExpression(Expression* expression) override;
+
+ private:
+  explicit TypingReseter(CompilationInfo* info);
+  CompilationInfo* info_;
+};
+}
+}  // namespace v8::internal
+
+#endif  // V8_TYPING_RESET_H_