Use linked hash map for broken alternative service queue.

net/http/http_server_properties.h

Index: net/http/http_server_properties.h
diff --git a/net/http/http_server_properties.h b/net/http/http_server_properties.h
index fcc89f7fd672a0bbbe82ed314d08e54ac3428b10..1030dbd44a07245ebf6f51c38e27c2059a998262 100644
--- a/net/http/http_server_properties.h
+++ b/net/http/http_server_properties.h
@@ -99,6 +99,11 @@ struct NET_EXPORT AlternativeService {
   AlternativeService& operator=(const AlternativeService& alternative_service) =
       default;
 
+  bool operator==(const AlternativeService& other) const {
+    return protocol == other.protocol && host == other.host &&
+           port == other.port;
+  }
+
   bool operator<(const AlternativeService& other) const {
     if (protocol != other.protocol)
       return protocol < other.protocol;