[Blimp] Refactor Blimp test engine with embedded test server and URL rewriting

blimp/engine/testing/app/blimp_url_rewriter.h

+// Copyright (c) 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 BLIMP_ENGINE_TESTING_APP_BLIMP_URL_REWRITER_H_
+#define BLIMP_ENGINE_TESTING_APP_BLIMP_URL_REWRITER_H_
+
+#include <string>
+
+#include "net/test/embedded_test_server/embedded_test_server.h"
+
+class GURL;
+
+namespace content {
+class BrowserContext;
+}
+
+namespace blimp {
+namespace engine {
+
+namespace test {
+
+extern std::unique_ptr<net::EmbeddedTestServer> g_ets_instance;
+
+bool HandleBlimpTestURL(GURL* url, content::BrowserContext* browser_context);
+}  // namespace test
+
+}  // namespace engine
+}  // namespace blimp
+#endif  //  BLIMP_ENGINE_TESTING_APP_BLIMP_URL_REWRITER_H_