Introduce WebInsecureRequestPolicy.

third_party/WebKit/public/platform/WebInsecureRequestPolicy.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 WebInsecureRequestPolicy_h
+#define WebInsecureRequestPolicy_h
+
+namespace blink {
+
+// TODO(mkwst): In an ideal world, the combined state would be the same as
+// "Upgrade". Once we're consistently upgrading all requests, we can replace
+// this bitfield-style representation with an enum. Until then, we need to
+// ensure that all relevant flags are set. https://crbug.com/617584
+using WebInsecureRequestPolicy = uint8_t;
+const WebInsecureRequestPolicy kLeaveInsecureRequestsAlone = 0;
+const WebInsecureRequestPolicy kUpgradeInsecureRequests = 1 << 0;
+const WebInsecureRequestPolicy kBlockAllMixedContent = 1 << 1;
+
+} // namespace blink
+
+#endif // WebInsecureRequestPolicy_h