Add a whitelist for QUIC hosts.

net/url_request/url_request_context_builder.h

Index: net/url_request/url_request_context_builder.h
diff --git a/net/url_request/url_request_context_builder.h b/net/url_request/url_request_context_builder.h
index 5b70b4cd149658639d0859ef29b7ea62cb2e966c..0a58c817961cbed8e02fb25f819dd46067a20159 100644
--- a/net/url_request/url_request_context_builder.h
+++ b/net/url_request/url_request_context_builder.h
@@ -16,6 +16,7 @@
 
 #include <stdint.h>
 #include <string>
+#include <unordered_map>
 #include <utility>
 
 #include "base/files/file_path.h"
@@ -90,6 +91,7 @@ class NET_EXPORT URLRequestContextBuilder {
     bool quic_store_server_configs_in_properties;
     bool quic_delay_tcp_race;
     int quic_max_number_of_lossy_connections;
+    std::unordered_set<std::string> quic_host_whitelist;
     float quic_packet_loss_threshold;
     int quic_idle_connection_timeout_seconds;
     QuicTagVector quic_connection_options;
@@ -223,6 +225,11 @@ class NET_EXPORT URLRequestContextBuilder {
         quic_idle_connection_timeout_seconds;
   }
 
+  void set_quic_host_whitelist(
+      const std::unordered_set<std::string>& quic_host_whitelist) {
+    http_network_session_params_.quic_host_whitelist = quic_host_whitelist;
+  }
+
   void set_throttling_enabled(bool throttling_enabled) {
     throttling_enabled_ = throttling_enabled;
   }