Create extensions_test_support build target

extensions/common/test_util.h

+// Copyright 2013 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 EXTENSIONS_COMMON_TEST_UTIL_H_
+#define EXTENSIONS_COMMON_TEST_UTIL_H_
+
+#include <string>
+
+#include "base/memory/ref_counted.h"
+
+namespace extensions {
+class Extension;
+class ExtensionBuilder;
+
+namespace test_util {
+
+// Adds an extension manifest to a builder.
+ExtensionBuilder& BuildExtension(ExtensionBuilder& builder);
+
+// Return a very simple extension with a given |id|.
+scoped_refptr<Extension> CreateExtensionWithID(const std::string& id);
+
+}  // namespace test_util
+}  // namespace extensions
+
+#endif  // EXTENSIONS_COMMON_TEST_UTIL_H_