[inspector] use own copy of third_party/inspector_protocol

third_party/inspector_protocol/lib/Forward_h.template

+// Copyright 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 {{"_".join(config.protocol.namespace)}}_Forward_h
+#define {{"_".join(config.protocol.namespace)}}_Forward_h
+
+{% if config.lib.export_header %}
+#include {{format_include(config.lib.export_header)}}
+{% endif %}
+#include {{format_include(config.lib.platform_header)}}
+#include {{format_include(config.lib.string_header)}}
+
+#include <vector>
+
+{% for namespace in config.protocol.namespace %}
+namespace {{namespace}} {
+{% endfor %}
+
+template<typename T> class Array;
+class DictionaryValue;
+using ErrorString = String;
+class ErrorSupport;
+class FundamentalValue;
+class ListValue;
+template<typename T> class Maybe;
+class Object;
+class SerializedValue;
+class StringValue;
+class UberDispatcher;
+class Value;
+
+{% for namespace in config.protocol.namespace %}
+} // namespace {{namespace}}
+{% endfor %}
+
+#endif // !defined({{"_".join(config.protocol.namespace)}}_Forward_h)