Make extensions DSE persistent in browser prefs

components/search_engines/search_engines_test_util.h

Index: components/search_engines/search_engines_test_util.h
diff --git a/components/search_engines/search_engines_test_util.h b/components/search_engines/search_engines_test_util.h
new file mode 100644
index 0000000000000000000000000000000000000000..10ecec039ccfd43176d76eca3cdcdc1db08c9eb6
--- /dev/null
+++ b/components/search_engines/search_engines_test_util.h
@@ -0,0 +1,39 @@
+// Copyright 2016 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.
+
+#ifndef COMPONENTS_SEARCH_ENGINES_SEARCH_ENGINES_TEST_UTIL_H_
+#define COMPONENTS_SEARCH_ENGINES_SEARCH_ENGINES_TEST_UTIL_H_
+
+#include <memory>
+#include <string>
+
+struct TemplateURLData;
+
+namespace sync_preferences {
+class TestingPrefServiceSyncable;
+}
+
+// Generates a TemplateURLData structure useful for tests filled with values
+// autogenerated from |provider_name|.
+std::unique_ptr<TemplateURLData> GenerateDummyTemplateURLData(
+    const std::string& provider_name);
+
+// Checks that the two TemplateURLs are similar. Does not check the id, the
+// date_created or the last_modified time.  Neither pointer should be null.
+void ExpectSimilar(const TemplateURLData* expected,
+                   const TemplateURLData* actual);
+
+// Writes default search engine |extension_data| into the extension-controlled
+// preference in |prefs|.
+void SetExtensionDefaultSearchInPrefs(
+    sync_preferences::TestingPrefServiceSyncable* prefs,
+    const TemplateURLData& extension_data,
+    const std::string& extension_id);
+
+// Removes the extension-controlled default search engine preference from
+// |prefs|.
+void RemoveExtensionDefaultSearchFromPrefs(
+    sync_preferences::TestingPrefServiceSyncable* prefs);
+
+#endif  // COMPONENTS_SEARCH_ENGINES_SEARCH_ENGINES_TEST_UTIL_H_