html_viewer: Add DevToolsAgentImpl.

components/devtools_service/public/cpp/switches.cc

Index: components/devtools_service/public/cpp/switches.cc
diff --git a/components/devtools_service/public/cpp/switches.cc b/components/devtools_service/public/cpp/switches.cc
new file mode 100644
index 0000000000000000000000000000000000000000..0a1d8ea4bfa0b10186b02389583defc5d27c2237
--- /dev/null
+++ b/components/devtools_service/public/cpp/switches.cc
@@ -0,0 +1,12 @@
+// 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.
+
+#include "components/devtools_service/public/cpp/switches.h"
+
+namespace devtools_service {
+
+// Enables remote debug over HTTP on the specified port.
+const char kRemoteDebuggingPort[] = "remote-debugging-port";
+
+}  // namespace devtools_service