HostResolver is exposed to plugin.

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 81a0690a8072e4ff32b543ff058dac34258dd023..51713efeb01f0f6e6015d2c77f6000a55a4e09a5 100644
--- a/webkit/plugins/ppapi/mock_plugin_delegate.cc
+++ b/webkit/plugins/ppapi/mock_plugin_delegate.cc
@@ -314,6 +314,20 @@ void MockPluginDelegate::TCPServerSocketStopListening(uint32 real_socket_id,
                                                       uint32 temp_socket_id) {
 }
 
+void MockPluginDelegate::RegisterHostResolver(
+    ::ppapi::PPB_HostResolver_Shared* host_resolver,
+    uint32 host_resolver_id) {
+}
+
+void MockPluginDelegate::HostResolverResolve(
+    uint32 host_resolver_id,
+    const ::ppapi::HostPortPair& host_port,
+    const PP_HostResolver_Private_Hint* hint) {
+}
+
+void MockPluginDelegate::UnregisterHostResolver(uint32 host_resolver_id) {
+}
+
 bool MockPluginDelegate::AddNetworkListObserver(
     webkit_glue::NetworkListObserver* observer) {
   return false;