When parsing cookie expiration times, saturate out of range dates

net/cookies/canonical_cookie.h

Index: net/cookies/canonical_cookie.h
diff --git a/net/cookies/canonical_cookie.h b/net/cookies/canonical_cookie.h
index 4102299e4251101ec92e824a5bef2b860cf4efb2..2ef9131e1a60f9fba6a7653ef7634ec5a054cd6d 100644
--- a/net/cookies/canonical_cookie.h
+++ b/net/cookies/canonical_cookie.h
@@ -139,6 +139,8 @@ class NET_EXPORT CanonicalCookie {
   std::string DebugString() const;
 
   static std::string CanonPath(const GURL& url, const ParsedCookie& pc);
+
+  // Returns a "null" time if expiration was unspecified or invalid.
   static base::Time CanonExpiration(const ParsedCookie& pc,
                                     const base::Time& current,
                                     const base::Time& server_time);