Handle disabling data reduction proxy for all platforms.

chrome/browser/net/spdyproxy/data_reduction_proxy_chrome_configurator.h

Index: chrome/browser/net/spdyproxy/data_reduction_proxy_chrome_configurator.h
diff --git a/chrome/browser/net/spdyproxy/data_reduction_proxy_chrome_configurator.h b/chrome/browser/net/spdyproxy/data_reduction_proxy_chrome_configurator.h
index 72051708f584d22c2c25363b4efefa6685496208..9b68d1b15b25c0a2714fce1fd7354f81f0a65747 100644
--- a/chrome/browser/net/spdyproxy/data_reduction_proxy_chrome_configurator.h
+++ b/chrome/browser/net/spdyproxy/data_reduction_proxy_chrome_configurator.h
@@ -32,6 +32,11 @@ class DataReductionProxyChromeConfigurator
       scoped_refptr<base::SequencedTaskRunner> network_task_runner);
   ~DataReductionProxyChromeConfigurator() override;
 
+  // Removes the data reduction proxy configuration from the proxy preference.
+  // This disables use of the data reduction proxy. This method is public to
+  // disable the proxy on incognito. Disable() should be used otherwise.
+  static void DisableInProxyConfigPref(PrefService* prefs);
+
   void Enable(bool primary_restricted,
               bool fallback_restricted,
               const std::string& primary_origin,
@@ -61,6 +66,10 @@ class DataReductionProxyChromeConfigurator
  private:
   FRIEND_TEST_ALL_PREFIXES(DataReductionProxyConfigTest, TestBypassList);
 
+  // Check whether the |proxy_rules| contain any of the data reduction proxies.
+  static bool ContainsDataReductionProxy(
+      const net::ProxyConfig::ProxyRules& proxy_rules);
+
   PrefService* prefs_;
   scoped_refptr<base::SequencedTaskRunner> network_task_runner_;