Persist the alternate protocol as a string not an int to allow the enum to be changed without affec…

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 ea80eee17380d0d62d927c1d8b91b0372bbb9d60..db47a9f26dd5765feb7c733959d12fd667541278 100644
--- a/net/http/http_server_properties.h
+++ b/net/http/http_server_properties.h
@@ -24,6 +24,10 @@ enum AlternateProtocol {
   UNINITIALIZED_ALTERNATE_PROTOCOL,
 };
 
+NET_EXPORT const char* AlternateProtocolToString(AlternateProtocol protocol);
+NET_EXPORT AlternateProtocol AlternateProtocolFromString(
+    const std::string& protocol);
+
 struct NET_EXPORT PortAlternateProtocolPair {
   bool Equals(const PortAlternateProtocolPair& other) const {
     return port == other.port && protocol == other.protocol;