Refactor client cert private key handling.

content/public/browser/content_browser_client.h

Index: content/public/browser/content_browser_client.h
diff --git a/content/public/browser/content_browser_client.h b/content/public/browser/content_browser_client.h
index e2b1af451874ae533cc4d2df1835e8b0381441c2..3b49bad78c8fb8d770449a12cd939aebd3162f4f 100644
--- a/content/public/browser/content_browser_client.h
+++ b/content/public/browser/content_browser_client.h
@@ -73,14 +73,14 @@ struct BindSourceInfo;
 }
 
 namespace net {
+class ClientCertIdentity;
+using ClientCertIdentityList = std::vector<std::unique_ptr<ClientCertIdentity>>;
 class CookieOptions;
 class NetLog;
 class SSLCertRequestInfo;
 class SSLInfo;
 class URLRequest;
 class URLRequestContext;
-class X509Certificate;
-typedef std::vector<scoped_refptr<X509Certificate>> CertificateList;
 }
 
 namespace rappor {
@@ -482,7 +482,7 @@ class CONTENT_EXPORT ContentBrowserClient {
   virtual void SelectClientCertificate(
       WebContents* web_contents,
       net::SSLCertRequestInfo* cert_request_info,
-      net::CertificateList client_certs,
+      net::ClientCertIdentityList client_certs,
       std::unique_ptr<ClientCertificateDelegate> delegate);
 
   // Returns a class to get notifications about media event. The embedder can