Create TranslateModelService and Factory

Implement the service that will handle loading TFLite models
needed for the translate service in Chrome.

Bug: 1151404
Change-Id: Ibcf242d7d4d54e032fd980fd244247bc1196fc69
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2553526Reviewed-by: Scott Little <sclittle@chromium.org>
Reviewed-by: Sophie Chang <sophiechang@chromium.org>
Reviewed-by: Tarun Bansal <tbansal@chromium.org>
Commit-Queue: Michael Crouse <mcrouse@chromium.org>
Cr-Commit-Position: refs/heads/master@{#833569}

chrome/browser/BUILD.gn

@@ -1839,6 +1839,10 @@ static_library("browser") {
     "translate/chrome_translate_client.h",
     "translate/translate_accept_languages_factory.cc",
     "translate/translate_accept_languages_factory.h",
+    "translate/translate_model_service_factory.cc",
+    "translate/translate_model_service_factory.h",
+    "translate/translate_model_service_impl.cc",
+    "translate/translate_model_service_impl.h",
     "translate/translate_ranker_factory.cc",
     "translate/translate_ranker_factory.h",
     "translate/translate_ranker_metrics_provider.cc",

chrome/browser/translate/translate_model_service_browsertest.cc

+// Copyright 2020 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 "base/run_loop.h"
+#include "base/test/scoped_feature_list.h"
+#include "chrome/browser/profiles/profile.h"
+#include "chrome/browser/translate/translate_model_service_factory.h"
+#include "chrome/browser/ui/browser.h"
+#include "chrome/test/base/in_process_browser_test.h"
+#include "components/translate/core/common/translate_util.h"
+#include "content/public/test/browser_test.h"
+#include "testing/gtest/include/gtest/gtest.h"
+
+using TranslateModelServiceDisabledBrowserTest = InProcessBrowserTest;
+
+IN_PROC_BROWSER_TEST_F(TranslateModelServiceDisabledBrowserTest,
+                       TranslateModelServiceDisabled) {
+  EXPECT_FALSE(
+      TranslateModelServiceFactory::GetForProfile(browser()->profile()));
+}
+
+class TranslateModelServiceBrowserTest
+    : public TranslateModelServiceDisabledBrowserTest {
+ public:
+  TranslateModelServiceBrowserTest() {
+    scoped_feature_list_.InitAndEnableFeature(
+        translate::kTFLiteLanguageDetectionEnabled);
+  }
+
+  ~TranslateModelServiceBrowserTest() override = default;
+
+ private:
+  base::test::ScopedFeatureList scoped_feature_list_;
+};
+
+IN_PROC_BROWSER_TEST_F(TranslateModelServiceBrowserTest,
+                       TranslateModelServiceEnabled) {
+  EXPECT_TRUE(
+      TranslateModelServiceFactory::GetForProfile(browser()->profile()));
+}
+
+IN_PROC_BROWSER_TEST_F(TranslateModelServiceBrowserTest,
+                       TranslateModelServiceEnabled_OffTheRecord) {
+  EXPECT_TRUE(TranslateModelServiceFactory::GetForProfile(
+      browser()->profile()->GetPrimaryOTRProfile()));
+}

chrome/browser/translate/translate_model_service_factory.cc

+// Copyright 2020 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/translate/translate_model_service_factory.h"
+
+#include "chrome/browser/profiles/incognito_helpers.h"
+#include "chrome/browser/profiles/profile.h"
+#include "chrome/browser/translate/translate_model_service_impl.h"
+#include "components/keyed_service/content/browser_context_dependency_manager.h"
+#include "components/translate/core/common/translate_util.h"
+#include "content/public/browser/browser_context.h"
+
+// static
+TranslateModelServiceImpl* TranslateModelServiceFactory::GetForProfile(
+    Profile* profile) {
+  if (translate::IsTFLiteLanguageDetectionEnabled()) {
+    return static_cast<TranslateModelServiceImpl*>(
+        GetInstance()->GetServiceForBrowserContext(profile, true));
+  }
+  return nullptr;
+}
+
+// static
+TranslateModelServiceFactory* TranslateModelServiceFactory::GetInstance() {
+  static base::NoDestructor<TranslateModelServiceFactory> factory;
+  return factory.get();
+}
+
+TranslateModelServiceFactory::TranslateModelServiceFactory()
+    : BrowserContextKeyedServiceFactory(
+          "TranslateModelService",
+          BrowserContextDependencyManager::GetInstance()) {}
+
+TranslateModelServiceFactory::~TranslateModelServiceFactory() = default;
+
+KeyedService* TranslateModelServiceFactory::BuildServiceInstanceFor(
+    content::BrowserContext* context) const {
+  return new TranslateModelServiceImpl();
+}
+
+content::BrowserContext* TranslateModelServiceFactory::GetBrowserContextToUse(
+    content::BrowserContext* context) const {
+  // Use the original profile's TranslateModelService, even in Incognito mode.
+  return chrome::GetBrowserContextRedirectedInIncognito(context);
+}

chrome/browser/translate/translate_model_service_factory.h

+// Copyright 2020 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.
+
+#ifndef CHROME_BROWSER_TRANSLATE_TRANSLATE_MODEL_SERVICE_FACTORY_H_
+#define CHROME_BROWSER_TRANSLATE_TRANSLATE_MODEL_SERVICE_FACTORY_H_
+
+#include "base/macros.h"
+#include "base/no_destructor.h"
+#include "components/keyed_service/content/browser_context_keyed_service_factory.h"
+
+namespace content {
+class BrowserContext;
+}  // namespace content
+
+class TranslateModelServiceImpl;
+class Profile;
+
+// LazyInstance that owns all TranslateModelService(s) and associates
+// them with Profiles.
+class TranslateModelServiceFactory : public BrowserContextKeyedServiceFactory {
+ public:
+  // Gets the TranslateModelService for the profile.
+  //
+  // Returns null if the features that allow for this to provide useful
+  // information are disabled.
+  static TranslateModelServiceImpl* GetForProfile(Profile* profile);
+
+  // Gets the LazyInstance that owns all TranslateModelService(s).
+  static TranslateModelServiceFactory* GetInstance();
+
+ private:
+  friend base::NoDestructor<TranslateModelServiceFactory>;
+
+  TranslateModelServiceFactory();
+  ~TranslateModelServiceFactory() override;
+
+  // BrowserContextKeyedServiceFactory:
+  KeyedService* BuildServiceInstanceFor(
+      content::BrowserContext* context) const override;
+  content::BrowserContext* GetBrowserContextToUse(
+      content::BrowserContext* context) const override;
+};
+
+#endif  //  CHROME_BROWSER_TRANSLATE_TRANSLATE_MODEL_SERVICE_FACTORY_H_

chrome/browser/translate/translate_model_service_impl.cc

+// Copyright 2020 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/translate/translate_model_service_impl.h"
+
+#include "base/files/file.h"
+#include "base/optional.h"
+
+TranslateModelServiceImpl::TranslateModelServiceImpl() {
+  // TODO(crbug.com/1151407): Register with the Optimiziation Guide for the
+  // language detection model.
+}
+
+TranslateModelServiceImpl::~TranslateModelServiceImpl() = default;
+
+base::Optional<base::File>
+TranslateModelServiceImpl::GetLanguageDetectionModelFile() {
+  // TODO(crbug.com/1151406): Implement loading the model on a background thread
+  // and return it for use by translate.
+  return base::nullopt;
+}

chrome/browser/translate/translate_model_service_impl.h

+// Copyright 2020 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.
+
+#ifndef CHROME_BROWSER_TRANSLATE_TRANSLATE_MODEL_SERVICE_IMPL_H_
+#define CHROME_BROWSER_TRANSLATE_TRANSLATE_MODEL_SERVICE_IMPL_H_
+
+#include "components/keyed_service/core/keyed_service.h"
+#include "components/translate/core/browser/translate_model_service.h"
+
+// Service that manages models required to support translation in the browser.
+class TranslateModelServiceImpl : public KeyedService,
+                                  public translate::TranslateModelService {
+ public:
+  TranslateModelServiceImpl();
+  ~TranslateModelServiceImpl() override;
+
+  // translate::TranslateModelService:
+  base::Optional<base::File> GetLanguageDetectionModelFile() override;
+};
+
+#endif  // CHROME_BROWSER_TRANSLATE_TRANSLATE_MODEL_SERVICE_IMPL_H_

chrome/test/BUILD.gn

@@ -1382,6 +1382,7 @@ if (!is_android) {
       "../browser/tracing/chrome_tracing_delegate_browsertest.cc",
       "../browser/translate/language_detection_service_browsertest.cc",
       "../browser/translate/translate_manager_browsertest.cc",
+      "../browser/translate/translate_model_service_browsertest.cc",
       "../browser/ui/ask_google_for_suggestions_dialog_browsertest.cc",
       "../browser/ui/autofill/payments/card_unmask_prompt_view_browsertest.cc",
       "../browser/ui/autofill/payments/card_unmask_prompt_view_tester.h",

components/translate/core/browser/BUILD.gn

@@ -29,6 +29,7 @@ static_library("browser") {
     "translate_metrics_logger.h",
     "translate_metrics_logger_impl.cc",
     "translate_metrics_logger_impl.h",
+    "translate_model_service.h",
     "translate_prefs.cc",
     "translate_prefs.h",
     "translate_ranker.h",

components/translate/core/browser/translate_model_service.h

+// Copyright 2020 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.
+
+#ifndef COMPONENTS_TRANSLATE_CORE_BROWSER_TRANSLATE_MODEL_SERVICE_H_
+#define COMPONENTS_TRANSLATE_CORE_BROWSER_TRANSLATE_MODEL_SERVICE_H_
+
+#include "base/optional.h"
+
+namespace base {
+class File;
+}  // namespace base
+
+namespace translate {
+
+// Service that manages models required to support translation in the browser.
+class TranslateModelService {
+ public:
+  TranslateModelService() = default;
+
+  // Returns a loaded file containing the TFLite model capable of detecting the
+  // language of a web page's text.
+  virtual base::Optional<base::File> GetLanguageDetectionModelFile() = 0;
+
+ protected:
+  virtual ~TranslateModelService() = default;
+};
+
+}  //  namespace translate
+
+#endif  // COMPONENTS_TRANSLATE_CORE_BROWSER_TRANSLATE_MODEL_SERVICE_H_

components/translate/core/common/translate_util.cc

@@ -25,6 +25,9 @@ const char kSecurityOrigin[] = "https://translate.googleapis.com/";
 const base::Feature kTranslateSubFrames{"TranslateSubFrames",
                                         base::FEATURE_DISABLED_BY_DEFAULT};
 
+const base::Feature kTFLiteLanguageDetectionEnabled{
+    "TFLiteLanguageDetectionEnabled", base::FEATURE_DISABLED_BY_DEFAULT};
+
 GURL GetTranslateSecurityOrigin() {
   std::string security_origin(kSecurityOrigin);
   base::CommandLine* command_line = base::CommandLine::ForCurrentProcess();
@@ -45,4 +48,8 @@ bool IsSubFrameLanguageDetectionEnabled() {
              kTranslateSubFrames, kDetectLanguageInSubFrames, true);
 }
 
+bool IsTFLiteLanguageDetectionEnabled() {
+  return base::FeatureList::IsEnabled(kTFLiteLanguageDetectionEnabled);
+}
+
 }  // namespace translate

components/translate/core/common/translate_util.h

@@ -14,6 +14,9 @@ namespace translate {
 // main frame.
 extern const base::Feature kTranslateSubFrames;
 
+// Controls whether the TFLite-based language detection is enabled.
+extern const base::Feature kTFLiteLanguageDetectionEnabled;
+
 // Isolated world sets following security-origin by default.
 extern const char kSecurityOrigin[];
 
@@ -27,6 +30,9 @@ bool IsSubFrameTranslationEnabled();
 // Return whether sub frame language detection is enabled.
 bool IsSubFrameLanguageDetectionEnabled();
 
+// Return whether TFLIte-based language detection is enabled.
+bool IsTFLiteLanguageDetectionEnabled();
+
 }  // namespace translate
 
 #endif  // COMPONENTS_TRANSLATE_CORE_COMMON_TRANSLATE_UTIL_H_