net: add DNS certificate revocation experiment.

chrome/browser/net/chrome_network_delegate.h

Index: chrome/browser/net/chrome_network_delegate.h
diff --git a/chrome/browser/net/chrome_network_delegate.h b/chrome/browser/net/chrome_network_delegate.h
index a582c388f1dfee223c44229f80cc69d40481944c..7abf351a06032bd179e7e4a2b7192d8d13c24e4e 100644
--- a/chrome/browser/net/chrome_network_delegate.h
+++ b/chrome/browser/net/chrome_network_delegate.h
@@ -9,6 +9,7 @@
 #include "base/basictypes.h"
 #include "base/compiler_specific.h"
 #include "base/memory/ref_counted.h"
+#include "base/time.h"
 #include "net/base/network_delegate.h"
 
 class CookieSettings;
@@ -23,6 +24,10 @@ namespace policy {
 class URLBlacklistManager;
 }
 
+namespace net {
+class DnsRRResolver;
+}
+
 // ChromeNetworkDelegate is the central point from within the chrome code to
 // add hooks into the network stack.
 class ChromeNetworkDelegate : public net::NetworkDelegate {
@@ -47,6 +52,8 @@ class ChromeNetworkDelegate : public net::NetworkDelegate {
   static void InitializeReferrersEnabled(BooleanPrefMember* enable_referrers,
                                          PrefService* pref_service);
 
+  static void EnableComodoDNSExperiment();
+
  private:
   // NetworkDelegate implementation.
   virtual int OnBeforeURLRequest(net::URLRequest* request,
@@ -95,6 +102,9 @@ class ChromeNetworkDelegate : public net::NetworkDelegate {
   // Weak, owned by our owner.
   const policy::URLBlacklistManager* url_blacklist_manager_;
 
+  scoped_ptr<net::DnsRRResolver> dnsrr_resolver_;
+  base::TimeTicks last_comodo_resolution_time_;
+
   DISALLOW_COPY_AND_ASSIGN(ChromeNetworkDelegate);
 };