| // Copyright 2017 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 "android_webview/browser/aw_field_trial_creator.h" |
| |
| #include "android_webview/browser/aw_metrics_service_client.h" |
| #include "base/base_switches.h" |
| #include "base/feature_list.h" |
| #include "base/path_service.h" |
| #include "base/strings/string_split.h" |
| #include "cc/base/switches.h" |
| #include "components/prefs/in_memory_pref_store.h" |
| #include "components/prefs/pref_registry_simple.h" |
| #include "components/prefs/pref_service.h" |
| #include "components/prefs/pref_service_factory.h" |
| #include "components/variations/entropy_provider.h" |
| #include "components/variations/pref_names.h" |
| #include "content/public/common/content_switches.h" |
| |
| namespace android_webview { |
| namespace { |
| |
| // TODO(kmilka): Update to work properly in environments both with and without |
| // UMA enabled. |
| std::unique_ptr<const base::FieldTrial::EntropyProvider> |
| CreateLowEntropyProvider() { |
| return std::unique_ptr<const base::FieldTrial::EntropyProvider>( |
| // Since variations are only enabled for users opted in to UMA, it is |
| // acceptable to use the SHA1EntropyProvider for randomization. |
| new metrics::SHA1EntropyProvider( |
| // Synchronous read of the client id is permitted as it is fast |
| // enough to have minimal impact on startup time, and is behind the |
| // webview-enable-finch flag. |
| android_webview::AwMetricsServiceClient::GetClientId())); |
| } |
| |
| // Synchronous read of variations data is permitted as it is fast |
| // enough to have minimal impact on startup time, and is behind the |
| // webview-enable-finch flag. |
| bool ReadVariationsSeedDataFromFile(PrefService* local_state) { |
| // TODO(kmilka): The data read is being moved to java and the data will be |
| // passed in via JNI. |
| return false; |
| } |
| |
| } // anonymous namespace |
| |
| AwFieldTrialCreator::AwFieldTrialCreator() |
| : aw_field_trials_(base::MakeUnique<AwFieldTrials>()) {} |
| |
| AwFieldTrialCreator::~AwFieldTrialCreator() {} |
| |
| std::unique_ptr<PrefService> AwFieldTrialCreator::CreateLocalState() { |
| scoped_refptr<PrefRegistrySimple> pref_registry = |
| base::MakeRefCounted<PrefRegistrySimple>(); |
| |
| // Register the variations prefs with default values that must be overridden. |
| pref_registry->RegisterInt64Pref(variations::prefs::kVariationsSeedDate, 0); |
| pref_registry->RegisterInt64Pref(variations::prefs::kVariationsLastFetchTime, |
| 0); |
| pref_registry->RegisterStringPref(variations::prefs::kVariationsCountry, |
| std::string()); |
| pref_registry->RegisterStringPref( |
| variations::prefs::kVariationsCompressedSeed, std::string()); |
| pref_registry->RegisterStringPref(variations::prefs::kVariationsSeedSignature, |
| std::string()); |
| pref_registry->RegisterListPref( |
| variations::prefs::kVariationsPermanentConsistencyCountry, |
| base::MakeUnique<base::ListValue>()); |
| |
| pref_service_factory_.set_user_prefs( |
| base::MakeRefCounted<InMemoryPrefStore>()); |
| return pref_service_factory_.Create(pref_registry.get()); |
| } |
| |
| void AwFieldTrialCreator::SetUpFieldTrials() { |
| if (!AwMetricsServiceClient::CheckSDKVersionForMetrics()) |
| return; |
| |
| AwMetricsServiceClient::LoadOrCreateClientId(); |
| |
| DCHECK(!field_trial_list_); |
| // Set the FieldTrialList singleton. |
| field_trial_list_ = |
| base::MakeUnique<base::FieldTrialList>(CreateLowEntropyProvider()); |
| |
| std::unique_ptr<PrefService> local_state = CreateLocalState(); |
| |
| if (!ReadVariationsSeedDataFromFile(local_state.get())) |
| return; |
| |
| variations::UIStringOverrider ui_string_overrider; |
| client_ = base::MakeUnique<AwVariationsServiceClient>(); |
| variations_field_trial_creator_ = |
| base::MakeUnique<variations::VariationsFieldTrialCreator>( |
| local_state.get(), client_.get(), ui_string_overrider); |
| |
| variations_field_trial_creator_->OverrideVariationsPlatform( |
| variations::Study::PLATFORM_ANDROID_WEBVIEW); |
| |
| // Unused by WebView, but required by |
| // VariationsFieldTrialCreator::SetupFieldTrials(). |
| std::vector<std::string> variation_ids; |
| std::set<std::string> unforceable_field_trials; |
| |
| // Populates the FieldTrialList singleton via the static member functions. |
| variations_field_trial_creator_->SetupFieldTrials( |
| cc::switches::kEnableGpuBenchmarking, switches::kEnableFeatures, |
| switches::kDisableFeatures, unforceable_field_trials, |
| CreateLowEntropyProvider(), base::MakeUnique<base::FeatureList>(), |
| &variation_ids, aw_field_trials_.get()); |
| } |
| |
| } // namespace android_webview |