Move some content url constants to /url.

net/base/url_constants.h

Index: net/base/url_constants.h
diff --git a/net/base/url_constants.h b/net/base/url_constants.h
new file mode 100644
index 0000000000000000000000000000000000000000..1ac9273a05cc90b9d5d97312bcfd0f083df49c54
--- /dev/null
+++ b/net/base/url_constants.h
@@ -0,0 +1,17 @@
+// 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.
+
+#ifndef NET_BASE_URL_CONSTANTS_H_
+#define NET_BASE_URL_CONSTANTS_H_
+
+#include "net/base/net_export.h"
+
+namespace net {
+
+NET_EXPORT extern const char kHttpScheme[];
+NET_EXPORT extern const char kHttpsScheme[];
+
+}  // namespace net
+
+#endif  // NET_BASE_URL_CONSTANTS_H_