Make CertificateProviderService vend ClientCertIdentities directly.

chrome/browser/certificate_manager_model.cc

Index: chrome/browser/certificate_manager_model.cc
diff --git a/chrome/browser/certificate_manager_model.cc b/chrome/browser/certificate_manager_model.cc
index d3c3ebf3e714312ef91b10bf3b8d1d8107bf6933..aa45bb0c584fac78aca0e0a6a6d11d96bd30e631 100644
--- a/chrome/browser/certificate_manager_model.cc
+++ b/chrome/browser/certificate_manager_model.cc
@@ -143,8 +143,11 @@ void CertificateManagerModel::RefreshSlotsUnlocked() {
 }
 
 void CertificateManagerModel::RefreshExtensionCertificates(
-    const net::CertificateList& new_certs) {
-  extension_cert_list_ = new_certs;
+    net::ClientCertIdentityList new_cert_identities) {
+  extension_cert_list_.clear();
+  extension_cert_list_.reserve(new_cert_identities.size());
+  for (const auto& identity : new_cert_identities)
+    extension_cert_list_.push_back(identity->certificate());
   observer_->CertificatesRefreshed();
   DVLOG(1) << "refresh finished for extension provided certificates";
 }