Add DataReductionProxy IPC to determine if the Data Reduction Proxy was used.

components/data_reduction_proxy/content/browser/data_reduction_proxy_message_filter.h

Index: components/data_reduction_proxy/content/browser/data_reduction_proxy_message_filter.h
diff --git a/components/data_reduction_proxy/content/browser/data_reduction_proxy_message_filter.h b/components/data_reduction_proxy/content/browser/data_reduction_proxy_message_filter.h
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index 0000000000000000000000000000000000000000..c7b3dcc4aef8b9b946770b8f7eab229336f5e8e5
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+++ b/components/data_reduction_proxy/content/browser/data_reduction_proxy_message_filter.h
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+// 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.
+
+#ifndef COMPONENTS_DATA_REDUCTION_PROXY_CONTENT_BROWSER_DATA_REDUCTION_PROXY_MESSAGE_FILTER_H_
+#define COMPONENTS_DATA_REDUCTION_PROXY_CONTENT_BROWSER_DATA_REDUCTION_PROXY_MESSAGE_FILTER_H_
+
+#include "base/macros.h"
+#include "content/public/browser/browser_message_filter.h"
+
+namespace net {
+class HostPortPair;
+}
+
+namespace data_reduction_proxy {
+
+class DataReductionProxyConfig;
+class DataReductionProxySettings;
+
+// An IPC listener to handle DataReductionProxy IPC messages from the renderer.
+class DataReductionProxyMessageFilter
+    : public content::BrowserMessageFilter {
+ public:
+  DataReductionProxyMessageFilter(DataReductionProxySettings* settings);
+
+  // Sets |response| to true if the |proxy_server| corresponds to a Data
+  // Reduction Proxy.
+  void OnIsDataReductionProxy(const net::HostPortPair& proxy_server,
+                              bool* response);
+
+ private:
+  ~DataReductionProxyMessageFilter() override;
+
+  // BrowserMessageFilter implementation.
+  bool OnMessageReceived(const IPC::Message& message) override;
+  void OverrideThreadForMessage(const IPC::Message& message,
+                                content::BrowserThread::ID* thread) override;
+
+  // Must outlive |this|.
+  DataReductionProxyConfig* config_;
+
+  DISALLOW_COPY_AND_ASSIGN(DataReductionProxyMessageFilter);
+};
+
+}  // namespace data_reduction_proxy
+
+#endif  // COMPONENTS_DATA_REDUCTION_PROXY_CONTENT_BROWSER_DATA_REDUCTION_PROXY_MESSAGE_FILTER_H_