[translate] Add translate ranker model loader.

components/translate/core/browser/translate_manager.cc

 // Copyright 2014 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 "components/translate/core/browser/translate_manager.h"
 
 #include <map>
 
 #include "base/bind.h"
 #include "base/command_line.h"
@@ skipping 113 matching lines @@
 std::unique_ptr<TranslateManager::TranslateErrorCallbackList::Subscription>
 TranslateManager::RegisterTranslateErrorCallback(
     const TranslateManager::TranslateErrorCallback& callback) {
   if (!g_callback_list_)
     g_callback_list_ = new TranslateErrorCallbackList;
   return g_callback_list_->Add(callback);
 }
 
 TranslateManager::TranslateManager(
     TranslateClient* translate_client,
+    TranslateRanker* translate_ranker,
     const std::string& accept_languages_pref_name)
     : page_seq_no_(0),
       accept_languages_pref_name_(accept_languages_pref_name),
       translate_client_(translate_client),
       translate_driver_(translate_client_->GetTranslateDriver()),
+      translate_ranker_(translate_ranker),
       language_state_(translate_driver_),
       translate_event_(base::MakeUnique<metrics::TranslateEventProto>()),
-      weak_method_factory_(this) {
-  if (TranslateRanker::IsEnabled())
-    TranslateRanker::GetInstance()->FetchModelData();  // Asynchronous.
-}
+      weak_method_factory_(this) {}
 
 base::WeakPtr<TranslateManager> TranslateManager::GetWeakPtr() {
   return weak_method_factory_.GetWeakPtr();
 }
 
 void TranslateManager::InitiateTranslation(const std::string& page_lang) {
   // TODO(rogerm): Remove ScopedTracker below once crbug.com/646711 is closed.
   tracked_objects::ScopedTracker tracking_profile(
       FROM_HERE_WITH_EXPLICIT_FUNCTION(
           "646711 translate::TranslateManager::InitiateTranslation"));
@@ skipping 68 matching lines @@
 
   InitTranslateEvent(language_code, target_lang, *translate_prefs);
 
   // Don't translate similar languages (ex: en-US to en).
   if (language_code == target_lang) {
     TranslateBrowserMetrics::ReportInitiationStatus(
         TranslateBrowserMetrics::INITIATION_STATUS_SIMILAR_LANGUAGES);
     return;
   }
 
+  bool ranker_should_offer_translation = true;

[groby-ooo-7-16, 2017/01/23 21:41:57]

Shouldn't this be initialized to false? If it doesn't enter the is-enabled
block, it shouldn't really offer translation?

[Roger McFarlane (Chromium), 2017/02/08 23:08:11]

In it's current incarnation, the ranker is as gate, not a trigger. I the ranker
is not enabled and/or it's enforcement is not enabled, the default/existing
behavior is to show the prompt, subject to the various other limiting heuristics
below.

To make it clearer, I've gotten rid of the generic IsEnabled() and retained just
the specific IsQueryEnabled(), IsEnforcementEnabled(), IsLoggingEnabled()
methods..

+  if (translate_ranker_->IsEnabled()) {
+    ranker_should_offer_translation = translate_ranker_->ShouldOfferTranslation(
+        *translate_prefs, language_code, target_lang);
+    translate_event_->set_ranker_request_timestamp_sec(
+        (base::TimeTicks::Now() - base::TimeTicks()).InSeconds());
+    translate_event_->set_ranker_version(translate_ranker_->GetModelVersion());
+    translate_event_->set_ranker_response(
+        ranker_should_offer_translation
+            ? metrics::TranslateEventProto::SHOW
+            : metrics::TranslateEventProto::DONT_SHOW);
+  }
+
   // Nothing to do if either the language Chrome is in or the language of the
   // page is not supported by the translation server.
   if (target_lang.empty() ||
       !TranslateDownloadManager::IsSupportedLanguage(language_code)) {
     TranslateBrowserMetrics::ReportInitiationStatus(
         TranslateBrowserMetrics::INITIATION_STATUS_LANGUAGE_IS_NOT_SUPPORTED);
     TranslateBrowserMetrics::ReportUnsupportedLanguageAtInitiation(
         language_code);
     RecordTranslateEvent(metrics::TranslateEventProto::UNSUPPORTED_LANGUAGE);
     return;
@@ skipping 50 matching lines @@
     return;
   }
 
   if (LanguageInULP(language_code)) {
     TranslateBrowserMetrics::ReportInitiationStatus(
         TranslateBrowserMetrics::INITIATION_STATUS_LANGUAGE_IN_ULP);
     RecordTranslateEvent(metrics::TranslateEventProto::DISABLED_BY_PREF);
     return;
   }
 
-  if (TranslateRanker::IsEnabled()) {
-    TranslateRanker* translate_ranker = TranslateRanker::GetInstance();
-    bool should_offer_translation = translate_ranker->ShouldOfferTranslation(
-        *translate_prefs, language_code, target_lang);
-    translate_event_->set_ranker_request_timestamp_sec(
-        (base::TimeTicks::Now() - base::TimeTicks()).InSeconds());
-    translate_event_->set_ranker_version(translate_ranker->GetModelVersion());
-    translate_event_->set_ranker_response(
-        should_offer_translation ? metrics::TranslateEventProto::SHOW
-                                 : metrics::TranslateEventProto::DONT_SHOW);
-    if (!should_offer_translation && TranslateRanker::IsEnforcementEnabled()) {
-      TranslateBrowserMetrics::ReportInitiationStatus(
-          TranslateBrowserMetrics::INITIATION_STATUS_ABORTED_BY_RANKER);
-      RecordTranslateEvent(metrics::TranslateEventProto::DISABLED_BY_RANKER);
-      return;
-    }
+  if (!ranker_should_offer_translation &&
+      translate_ranker_->IsEnforcementEnabled()) {
+    TranslateBrowserMetrics::ReportInitiationStatus(
+        TranslateBrowserMetrics::INITIATION_STATUS_ABORTED_BY_RANKER);
+    RecordTranslateEvent(metrics::TranslateEventProto::DISABLED_BY_RANKER);
+    return;
   }
 
   TranslateBrowserMetrics::ReportInitiationStatus(
       TranslateBrowserMetrics::INITIATION_STATUS_SHOW_INFOBAR);
 
   // Prompts the user if they want the page translated.
   translate_client_->ShowTranslateUI(translate::TRANSLATE_STEP_BEFORE_TRANSLATE,
                                      language_code,
                                      target_lang,
                                      TranslateErrors::NONE,
@@ skipping 265 matching lines @@
   translate_event_->set_event_type(metrics::TranslateEventProto::UNKNOWN);
   // TODO(rogerm): Populate the language list.
 }
 
 void TranslateManager::RecordTranslateEvent(int event_type) {
   DCHECK(metrics::TranslateEventProto::EventType_IsValid(event_type));
   translate_event_->set_event_type(
       static_cast<metrics::TranslateEventProto::EventType>(event_type));
   translate_event_->set_event_timestamp_sec(
       (base::TimeTicks::Now() - base::TimeTicks()).InSeconds());
-  TranslateRanker::GetInstance()->RecordTranslateEvent(*translate_event_);
+  translate_ranker_->AddTranslateEvent(std::move(translate_event_));
+  translate_event_ = base::MakeUnique<metrics::TranslateEventProto>();
 }
 
 }  // namespace translate