Implement plumbing for variations in feedback reports.

components/variations/variations_http_header_provider_unittest.cc

 // Copyright 2014 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.
 
 #include "components/variations/variations_http_header_provider.h"
 
 #include <string>
 
 #include "base/base64.h"
 #include "base/message_loop/message_loop.h"
@@ skipping 105 matching lines @@
 
   std::string variations = provider.GetClientDataHeader();
 
   std::set<VariationID> variation_ids;
   std::set<VariationID> trigger_ids;
   ASSERT_TRUE(ExtractVariationIds(variations, &variation_ids, &trigger_ids));
   EXPECT_TRUE(variation_ids.find(123) != variation_ids.end());
   EXPECT_TRUE(trigger_ids.find(456) != trigger_ids.end());
 }
 
+TEST_F(VariationsHttpHeaderProviderTest, GetVariationsString) {
+  base::MessageLoop loop;
+  base::FieldTrialList field_trial_list(nullptr);
+
+  CreateTrialAndAssociateId("t1", "g1", GOOGLE_WEB_PROPERTIES, 123);
+  CreateTrialAndAssociateId("t2", "g2", GOOGLE_WEB_PROPERTIES, 124);
+
+  VariationsHttpHeaderProvider provider;
+  provider.SetDefaultVariationIds("100,200");
+  EXPECT_EQ(" 100 123 124 200 ", provider.GetVariationsString());
+}
+
 }  // namespace variations