net: extract net/cert out of net/base

This introduces the following dependency of net/base on things outside:

net/base/openssl_client_key_store.cc:#include "net/cert/x509_certificate.h"

BUG=70818

Review URL: https://codereview.chromium.org/13006020

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@191450 0039d316-1c4b-4281-b951-d872f2087c98
diff --git a/net/ssl/ssl_client_auth_cache_unittest.cc b/net/ssl/ssl_client_auth_cache_unittest.cc
index 9a5c5c07..ef507e4 100644
--- a/net/ssl/ssl_client_auth_cache_unittest.cc
+++ b/net/ssl/ssl_client_auth_cache_unittest.cc
@@ -5,7 +5,7 @@
 #include "net/ssl/ssl_client_auth_cache.h"
 
 #include "base/time.h"
-#include "net/base/x509_certificate.h"
+#include "net/cert/x509_certificate.h"
 #include "testing/gtest/include/gtest/gtest.h"
 
 namespace net {