Verify alternative server certificate validity for origin.

net/socket/socket_test_util.cc

Index: net/socket/socket_test_util.cc
diff --git a/net/socket/socket_test_util.cc b/net/socket/socket_test_util.cc
index b905597a2aa2d5d079586126684c6adbf53d19a3..94d4385ee40678a818abcaa2cab3a875dca49c86 100644
--- a/net/socket/socket_test_util.cc
+++ b/net/socket/socket_test_util.cc
@@ -18,6 +18,7 @@
 #include "net/base/address_list.h"
 #include "net/base/auth.h"
 #include "net/base/load_timing_info.h"
+#include "net/base/test_data_directory.h"
 #include "net/http/http_network_session.h"
 #include "net/http/http_request_headers.h"
 #include "net/http/http_response_headers.h"
@@ -26,6 +27,7 @@
 #include "net/ssl/ssl_cert_request_info.h"
 #include "net/ssl/ssl_connection_status_flags.h"
 #include "net/ssl/ssl_info.h"
+#include "net/test/cert_test_util.h"
 #include "testing/gtest/include/gtest/gtest.h"
 
 #define NET_TRACE(level, s) VLOG(level) << s << __FUNCTION__ << "() "
@@ -295,6 +297,12 @@ void SSLSocketDataProvider::SetNextProto(NextProto proto) {
   next_proto = SSLClientSocket::NextProtoToString(proto);
 }
 
+void SSLSocketDataProvider::SetCertFromFile(const std::string& cert_filename) {
+  base::FilePath certs_dir = GetTestCertsDirectory();
+  cert = ImportCertFromFile(certs_dir, cert_filename);
+  ASSERT_NE(nullptr, cert.get());
+}
+
 DelayedSocketData::DelayedSocketData(
     int write_delay, MockRead* reads, size_t reads_count,
     MockWrite* writes, size_t writes_count)