It suffices to just forward-declare DnsCertProvenanceChecker

net/url_request/url_request_context.h

Index: net/url_request/url_request_context.h
===================================================================
--- net/url_request/url_request_context.h	(revision 86289)
+++ net/url_request/url_request_context.h	(working copy)
@@ -18,7 +18,6 @@
 #include "net/base/ssl_config_service.h"
 #include "net/base/transport_security_state.h"
 #include "net/ftp/ftp_auth_cache.h"
-#include "net/socket/dns_cert_provenance_checker.h"

[wtc, 2011/05/24 14:53:37]

We only need the forward declaration on line 26.

 
 namespace net {
 class CertVerifier;
@@ -31,7 +30,6 @@
 class HttpTransactionFactory;
 class NetworkDelegate;
 class ProxyService;
-class SSLConfigService;

[wtc, 2011/05/24 14:53:37]

We include "net/base/ssl_config_service.h" on line 18, so
this forward declaration is not necessary.

 class URLRequest;
 class URLRequestJobFactory;