Add experimental feature info to certificate reports

components/certificate_reporting/BUILD.gn

 # Copyright 2015 The Chromium Authors. All rights reserved.
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
 
 import("//third_party/protobuf/proto_library.gni")
 
 static_library("certificate_reporting") {
   sources = [
     "cert_logger.proto",
     "encrypted_cert_logger.proto",
     "error_report.cc",
     "error_report.h",
     "error_reporter.cc",
     "error_reporter.h",
   ]
 
   public_deps = [
     ":cert_logger_proto",
     ":encrypted_cert_logger_proto",
   ]
   deps = [
     "//base",
+    "//components/variations",
     "//crypto",
     "//net",
     "//url",
   ]
 }
 
 proto_library("cert_logger_proto") {
   sources = [
     "cert_logger.proto",
   ]
 }
 
 proto_library("encrypted_cert_logger_proto") {
   sources = [
     "encrypted_cert_logger.proto",
   ]
 }
 
 source_set("unit_tests") {
   testonly = true
   sources = [
     "error_report_unittest.cc",
     "error_reporter_unittest.cc",
   ]
 
   deps = [
     ":certificate_reporting",
     "//base",
+    "//base/test:test_support",
+    "//components/variations",
     "//net:test_support",
     "//testing/gtest",
   ]
 }