Revert of Remove SSLClientAuthHandler's RDH dependency.

content/public/browser/content_browser_client.cc

Index: content/public/browser/content_browser_client.cc
diff --git a/content/public/browser/content_browser_client.cc b/content/public/browser/content_browser_client.cc
index 4dd65b60e97d3000790d926c0cb2250513011217..a29c48d7f0f8e84cccab8cd8f9623fc0f9cbac08 100644
--- a/content/public/browser/content_browser_client.cc
+++ b/content/public/browser/content_browser_client.cc
@@ -167,14 +167,6 @@
 
 QuotaPermissionContext* ContentBrowserClient::CreateQuotaPermissionContext() {
   return NULL;
-}
-
-void ContentBrowserClient::SelectClientCertificate(
-    int render_process_id,
-    int render_frame_id,
-    net::SSLCertRequestInfo* cert_request_info,
-    const base::Callback<void(net::X509Certificate*)>& callback) {
-  callback.Run(NULL);
 }
 
 net::URLRequestContext* ContentBrowserClient::OverrideRequestContextForURL(