Add the PPAPI X509 Certificate interface and implementation.

webkit/plugins/ppapi/mock_plugin_delegate.cc

Index: webkit/plugins/ppapi/mock_plugin_delegate.cc
diff --git a/webkit/plugins/ppapi/mock_plugin_delegate.cc b/webkit/plugins/ppapi/mock_plugin_delegate.cc
index ab55d9746637c7d44f2e01588baf14aadcd155d2..78e3fc99f13b277d4ae8cd2de533e0cdf4cf1a43 100644
--- a/webkit/plugins/ppapi/mock_plugin_delegate.cc
+++ b/webkit/plugins/ppapi/mock_plugin_delegate.cc
@@ -328,6 +328,12 @@ void MockPluginDelegate::RemoveNetworkListObserver(
     webkit_glue::NetworkListObserver* observer) {
 }
 
+bool MockPluginDelegate::X509CertificateParseDER(
+    const std::vector<char>& der,
+    ::ppapi::PPB_X509Certificate_Fields* fields) {
+  return false;
+}
+
 int32_t MockPluginDelegate::ShowContextMenu(
     PluginInstance* instance,
     webkit::ppapi::PPB_Flash_Menu_Impl* menu,