Added data reduction proxy holdback experiment

chrome/browser/net/spdyproxy/data_reduction_proxy_settings_android.cc

 // Copyright 2013 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.
 
 #include "chrome/browser/net/spdyproxy/data_reduction_proxy_settings_android.h"
 
 #include "base/android/build_info.h"
 #include "base/android/jni_android.h"
 #include "base/android/jni_string.h"
 #include "base/bind.h"
@@ skipping 177 matching lines @@
     bool alternative_enabled,
     bool restricted,
     bool at_startup) {
   // Sanity check: If there's no fallback proxy, we can't do a restricted mode.
   std::string fallback = params()->fallback_origin().spec();
   if (fallback.empty() && enabled && restricted)
       enabled = false;
 
   LogProxyState(enabled, restricted, at_startup);
 
-  if (enabled) {
+  if (enabled && !params()->holdback()) {
     if (alternative_enabled) {
       configurator()->Enable(restricted,
                        !params()->fallback_allowed(),
                        params()->alt_origin().spec(),
                        params()->alt_fallback_origin().spec(),
                        params()->ssl_origin().spec());
     } else {
         configurator()->Enable(restricted,
                          !params()->fallback_allowed(),
                          params()->origin().spec(),
@@ skipping 25 matching lines @@
 
 
 
 // Used by generated jni code.
 static jlong Init(JNIEnv* env, jobject obj) {
   DataReductionProxySettingsAndroid* settings =
       DataReductionProxySettingsFactoryAndroid::GetForBrowserContext(
           ProfileManager::GetActiveUserProfile());
   return reinterpret_cast<intptr_t>(settings);
 }