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 a29c48d7f0f8e84cccab8cd8f9623fc0f9cbac08..4dd65b60e97d3000790d926c0cb2250513011217 100644
--- a/content/public/browser/content_browser_client.cc
+++ b/content/public/browser/content_browser_client.cc
@@ -169,6 +169,14 @@ 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(
     const GURL& url, ResourceContext* context) {
   return NULL;