Amortize data usage using TrafficStats on Android.

chrome/browser/io_thread.cc

 // Copyright (c) 2012 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/io_thread.h"
 
 #include <vector>
 
 #include "base/base64.h"
 #include "base/bind.h"
@@ skipping 25 matching lines @@
 #include "chrome/browser/net/connect_interceptor.h"
 #include "chrome/browser/net/dns_probe_service.h"
 #include "chrome/browser/net/proxy_service_factory.h"
 #include "chrome/common/channel_info.h"
 #include "chrome/common/chrome_content_client.h"
 #include "chrome/common/chrome_switches.h"
 #include "chrome/common/pref_names.h"
 #include "components/data_reduction_proxy/core/browser/data_reduction_proxy_prefs.h"
 #include "components/data_reduction_proxy/core/common/data_reduction_proxy_params.h"
 #include "components/data_reduction_proxy/core/common/data_reduction_proxy_pref_names.h"
+#include "components/data_usage/core/data_use_amortizer.h"
 #include "components/net_log/chrome_net_log.h"
 #include "components/policy/core/common/policy_service.h"
 #include "components/proxy_config/pref_proxy_config_tracker.h"
 #include "components/variations/variations_associated_data.h"
 #include "components/version_info/version_info.h"
 #include "content/public/browser/browser_thread.h"
 #include "content/public/browser/cookie_store_factory.h"
 #include "content/public/common/content_switches.h"
 #include "content/public/common/user_agent.h"
 #include "net/base/external_estimate_provider.h"
@@ skipping 52 matching lines @@
 #endif
 
 #if defined(USE_NSS_CERTS) || defined(OS_IOS)
 #include "net/cert_net/nss_ocsp.h"
 #endif
 
 #if defined(OS_ANDROID)
 #include "base/android/build_info.h"
 #include "chrome/browser/android/datausage/external_data_use_observer.h"
 #include "chrome/browser/android/net/external_estimate_provider_android.h"
+#include "components/data_usage/android/traffic_stats_amortizer.h"
 #endif
 
 #if defined(OS_CHROMEOS)
 #include "chrome/browser/chromeos/net/cert_verify_proc_chromeos.h"
 #include "chromeos/network/host_resolver_impl_chromeos.h"
 #endif
 
 using content::BrowserThread;
 
 class SafeBrowsingURLRequestContext;
@@ skipping 471 matching lines @@
       new LoggingNetworkChangeObserver(net_log_));
 
   // Setup the HistogramWatcher to run on the IO thread.
   net::NetworkChangeNotifier::InitHistogramWatcher();
 
 #if defined(ENABLE_EXTENSIONS)
   globals_->extension_event_router_forwarder =
       extension_event_router_forwarder_;
 #endif
 
+  scoped_ptr<data_usage::DataUseAmortizer> data_use_amortizer;
+#if defined(OS_ANDROID)
+  data_use_amortizer.reset(new data_usage::android::TrafficStatsAmortizer());

[bengr, 2015/11/10 18:12:50]

It would be better if you didn't specialize for Android here, and instead passed
this in via the IOThread constructor or Globals. Likewise for the
external_data_use_observer_.

[tbansal1, 2015/11/10 18:53:55]

Why can this not be constructed in DataUseAggregator constructor (instead of
IOthread constructing it and passing it)?

[sclittle, 2015/11/11 02:10:07]

I don't think I understand what you mean. It has to be specialized for Android
somewhere, and if it's specialized here, then no where else has to hold on to a
scoped_ptr<DataUseAmortizer>.

Plus, the aggregator takes ownership of the amortizer, so it would be an empty
scoped_ptr<DataUseAmortizer> in Globals/IOThread most of the time.

[sclittle, 2015/11/11 02:10:07]

Because the DataUseAggregator doesn't have visibility into the
components/data_usage/android directory, since that would be a cyclical
dependency.

[bengr, 2015/11/11 15:41:37]

I was hoping that you could set up the platform specialization in
ChromeBrowserMainParts::PreCreateThreadsImpl() or somewhere nearby, but it
doesn't look like there's an established pattern.

+#endif
+
   data_use_aggregator_.reset(new data_usage::DataUseAggregator(
       scoped_ptr<data_usage::DataUseAnnotator>(
-          new chrome_browser_data_usage::TabIdAnnotator())));
+          new chrome_browser_data_usage::TabIdAnnotator()),
+      data_use_amortizer.Pass()));
 
   // TODO(erikchen): Remove ScopedTracker below once http://crbug.com/466432
   // is fixed.
   tracked_objects::ScopedTracker tracking_profile3(
       FROM_HERE_WITH_EXPLICIT_FUNCTION(
           "466432 IOThread::InitAsync::ChromeNetworkDelegate"));
   scoped_ptr<ChromeNetworkDelegate> chrome_network_delegate(
       new ChromeNetworkDelegate(extension_event_router_forwarder(),
                                 &system_enable_referrers_));
   // By default, data usage is considered off the record.
@@ skipping 1035 matching lines @@
   globals->proxy_script_fetcher_url_request_job_factory = job_factory.Pass();
 
   context->set_job_factory(
       globals->proxy_script_fetcher_url_request_job_factory.get());
 
   // TODO(rtenneti): We should probably use HttpServerPropertiesManager for the
   // system URLRequestContext too. There's no reason this should be tied to a
   // profile.
   return context;
 }