Clang fix for http://codereview.chromium.org/7870011/

Appease the clang bot.

BUG=chromium-os:19908
TEST=clang bot succeeds
TBR=dmazzoni@chromium.org

Review URL: http://codereview.chromium.org/7845027

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@100770 0039d316-1c4b-4281-b951-d872f2087c98

chrome/browser/chromeos/cros/network_library.h

@@ -1590,6 +1590,7 @@ class NetworkLibrary {
   // VPNConfigData must be provided.
   struct VPNConfigData {
     VPNConfigData() {}
+    ~VPNConfigData() {}
     std::string psk;
     std::string server_ca_cert_nss_nickname;
     std::string client_cert_pkcs11_id;