Add net::CertificateReportSender for handling cert report sending

net/http/transport_security_state.h

Index: net/http/transport_security_state.h
diff --git a/net/http/transport_security_state.h b/net/http/transport_security_state.h
index 2f97d9d34e5a6a20be27b1bcb1b96bbbad56c187..6109381dcb1840016a40f0600ba380ec5630e4ed 100644
--- a/net/http/transport_security_state.h
+++ b/net/http/transport_security_state.h
@@ -46,6 +46,16 @@ class NET_EXPORT TransportSecurityState
     virtual ~Delegate() {}
   };
 
+  // An interface for asynchronously sending HPKP violation reports.
+  class ReportSender {
+   public:
+    // Sends the given serialized |report| to |report_uri|.
+    virtual void Send(const GURL& report_uri, const std::string& report) = 0;
+
+   protected:
+    virtual ~ReportSender() {}
+  };
+
   TransportSecurityState();
   ~TransportSecurityState();