Implement support for QUIC proxies in ProxyServer

net/proxy/proxy_info.h

Index: net/proxy/proxy_info.h
diff --git a/net/proxy/proxy_info.h b/net/proxy/proxy_info.h
index 243cbba80fd8fef9f152f52ef9bb98cab8a8c54b..336cb3a58881c2982f4d1a4b4d10d5e16597cdf7 100644
--- a/net/proxy/proxy_info.h
+++ b/net/proxy/proxy_info.h
@@ -75,6 +75,13 @@ class NET_EXPORT ProxyInfo {
     return proxy_server().is_http();
   }
 
+  // Returns true if the first valid proxy server is a quic proxy.
+  bool is_quic() const {
+    if (is_empty())
+      return false;
+    return proxy_server().is_quic();
+  }
+
   // Returns true if the first valid proxy server is a socks server.
   bool is_socks() const {
     if (is_empty())