[Cronet] Allow experimenting with Chrome's internal DNS resolver.

components/cronet/url_request_context_config.h

Index: components/cronet/url_request_context_config.h
diff --git a/components/cronet/url_request_context_config.h b/components/cronet/url_request_context_config.h
index 89e509ec6aba62eaaf3d2d76138f4980c65a30c6..29e1c85a71441b91ef890416335947aff7467196 100644
--- a/components/cronet/url_request_context_config.h
+++ b/components/cronet/url_request_context_config.h
@@ -14,6 +14,7 @@
 
 namespace net {
 class CertVerifier;
+class NetLog;
 class URLRequestContextBuilder;
 }  // namespace net
 
@@ -103,7 +104,8 @@ struct URLRequestContextConfig {
 
   // Configure |context_builder| based on |this|.
   void ConfigureURLRequestContextBuilder(
-      net::URLRequestContextBuilder* context_builder);
+      net::URLRequestContextBuilder* context_builder,
+      net::NetLog* net_log);
 
   // Enable QUIC.
   const bool enable_quic;