[CrOS Settings] Add SearchHandler interface and implementation.

This CL:
(1) Adds a SearchHandler Mojo interface, then implements it via a
    KeyedService.
(2) Hooks up this interface to the OS settings UI.

After this CL, it's possible for the settings JS code to make direct
calls into the service.

Bug: 1059099
Change-Id: I51fbdabdcd227a6004e4319038383cdf4ada9519
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2103523
Commit-Queue: Kyle Horimoto <khorimoto@chromium.org>
Reviewed-by: Daniel Cheng <dcheng@chromium.org>
Reviewed-by: James Cook <jamescook@chromium.org>
Reviewed-by: dpapad <dpapad@chromium.org>
Auto-Submit: Kyle Horimoto <khorimoto@chromium.org>
Cr-Commit-Position: refs/heads/master@{#752731}

chrome/browser/browser_resources.grd

@@ -447,6 +447,8 @@
         <include name="IDR_ADD_SUPERVISION_MOJOM_LITE_JS" file="${root_gen_dir}\chrome\browser\ui\webui\chromeos\add_supervision\add_supervision.mojom-lite.js" compress="gzip" use_base_dir="false" type="BINDATA" />
       </if>
       <if expr="chromeos">
+        <include name="IDR_OS_SETTINGS_SEARCH_MOJOM_LITE_JS" file="${root_gen_dir}\chrome\browser\ui\webui\settings\chromeos\search\search.mojom-lite.js" compress="gzip" use_base_dir="false" type="BINDATA" />
+        <include name="IDR_OS_SETTINGS_SEARCH_RESULT_ICON_MOJOM_LITE_JS" file="${root_gen_dir}\chrome\browser\ui\webui\settings\chromeos\search\search_result_icon.mojom-lite.js" compress="gzip" use_base_dir="false" type="BINDATA" />
         <include name="IDR_OS_SETTINGS_USER_ACTION_RECORDER_MOJOM_LITE_JS" file="${root_gen_dir}\chrome\browser\ui\webui\settings\chromeos\search\user_action_recorder.mojom-lite.js" compress="gzip" use_base_dir="false" type="BINDATA" />
       </if>
       <if expr="chromeos">

chrome/browser/chrome_browser_interface_binders.cc

@@ -130,6 +130,7 @@
 #include "chrome/browser/ui/webui/chromeos/multidevice_setup/multidevice_setup_dialog.h"
 #include "chrome/browser/ui/webui/chromeos/network_ui.h"
 #include "chrome/browser/ui/webui/settings/chromeos/os_settings_ui.h"
+#include "chrome/browser/ui/webui/settings/chromeos/search/search.mojom.h"
 #include "chrome/browser/ui/webui/settings/chromeos/search/user_action_recorder.mojom.h"
 #include "chromeos/components/help_app_ui/help_app_ui.h"
 #include "chromeos/components/help_app_ui/help_app_ui.mojom.h"
@@ -486,6 +487,10 @@ void PopulateChromeWebUIFrameBinders(
       chromeos::settings::mojom::UserActionRecorder,
       chromeos::settings::OSSettingsUI>(map);
 
+  RegisterWebUIControllerInterfaceBinder<
+      chromeos::settings::mojom::SearchHandler,
+      chromeos::settings::OSSettingsUI>(map);
+
   RegisterWebUIControllerInterfaceBinder<
       chromeos::cellular_setup::mojom::CellularSetup,
       chromeos::cellular_setup::CellularSetupDialogUI>(map);

chrome/browser/chromeos/BUILD.gn

@@ -3175,6 +3175,7 @@ source_set("unit_tests") {
     "../ui/webui/settings/chromeos/internet_handler_unittest.cc",
     "../ui/webui/settings/chromeos/multidevice_handler_unittest.cc",
     "../ui/webui/settings/chromeos/os_settings_localized_strings_provider_unittest.cc",
+    "../ui/webui/settings/chromeos/search/search_handler_unittest.cc",
     "../ui/webui/settings/chromeos/search/settings_user_action_tracker_unittest.cc",
   ]
   if (use_cups) {

chrome/browser/resources/settings/chromeos/BUILD.gn

@@ -37,8 +37,11 @@ if (optimize_webui) {
       "chrome://os-settings/app-management/image_info.mojom-lite.js",
       "chrome://os-settings/app-management/image.mojom-lite.js",
       "chrome://os-settings/app-management/types.mojom-lite.js",
+      "chrome://os-settings/search/search.mojom-lite.js",
+      "chrome://os-settings/search/search_result_icon.mojom-lite.js",
       "chrome://os-settings/search/user_action_recorder.mojom-lite.js",
       "chrome://resources/mojo/mojo/public/mojom/base/big_buffer.mojom.html",
+      "chrome://resources/mojo/mojo/public/mojom/base/string16.mojom.html",
       "chrome://resources/mojo/mojo/public/mojom/base/time.mojom.html",
     ]
 

chrome/browser/ui/BUILD.gn

@@ -2034,6 +2034,10 @@ jumbo_static_library("ui") {
       "webui/settings/chromeos/quick_unlock_handler.cc",
       "webui/settings/chromeos/quick_unlock_handler.h",
       "webui/settings/chromeos/search/search_concept.h",
+      "webui/settings/chromeos/search/search_handler.cc",
+      "webui/settings/chromeos/search/search_handler.h",
+      "webui/settings/chromeos/search/search_handler_factory.cc",
+      "webui/settings/chromeos/search/search_handler_factory.h",
       "webui/settings/chromeos/search/settings_user_action_tracker.cc",
       "webui/settings/chromeos/search/settings_user_action_tracker.h",
       "webui/settings/chromeos/server_printer_url_util.cc",

chrome/browser/ui/webui/settings/chromeos/os_settings_ui.cc

@@ -67,6 +67,8 @@
 #include "chrome/browser/ui/webui/settings/chromeos/plugin_vm_handler.h"
 #include "chrome/browser/ui/webui/settings/chromeos/pref_names.h"
 #include "chrome/browser/ui/webui/settings/chromeos/quick_unlock_handler.h"
+#include "chrome/browser/ui/webui/settings/chromeos/search/search_handler.h"
+#include "chrome/browser/ui/webui/settings/chromeos/search/search_handler_factory.h"
 #include "chrome/browser/ui/webui/settings/chromeos/search/settings_user_action_tracker.h"
 #include "chrome/browser/ui/webui/settings/chromeos/wallpaper_handler.h"
 #include "chrome/browser/ui/webui/settings/downloads_handler.h"
@@ -241,6 +243,11 @@ OSSettingsUI::OSSettingsUI(content::WebUI* web_ui)
   html_source->AddResourcePath(
       "search/user_action_recorder.mojom-lite.js",
       IDR_OS_SETTINGS_USER_ACTION_RECORDER_MOJOM_LITE_JS);
+  html_source->AddResourcePath(
+      "search/search_result_icon.mojom-lite.js",
+      IDR_OS_SETTINGS_SEARCH_RESULT_ICON_MOJOM_LITE_JS);
+  html_source->AddResourcePath("search/search.mojom-lite.js",
+                               IDR_OS_SETTINGS_SEARCH_MOJOM_LITE_JS);
 
   // AddOsLocalizedStrings must be added after AddBrowserLocalizedStrings
   // as repeated keys used by the OS strings should override the same keys
@@ -474,6 +481,12 @@ void OSSettingsUI::BindInterface(
       std::make_unique<SettingsUserActionTracker>(std::move(receiver));
 }
 
+void OSSettingsUI::BindInterface(
+    mojo::PendingReceiver<mojom::SearchHandler> receiver) {
+  SearchHandlerFactory::GetForProfile(Profile::FromWebUI(web_ui()))
+      ->BindInterface(std::move(receiver));
+}
+
 void OSSettingsUI::BindInterface(
     mojo::PendingReceiver<app_management::mojom::PageHandlerFactory> receiver) {
   if (!app_management_page_handler_factory_) {

chrome/browser/ui/webui/settings/chromeos/os_settings_ui.h

@@ -29,6 +29,10 @@ class PrefRegistrySyncable;
 namespace chromeos {
 namespace settings {
 
+namespace mojom {
+class SearchHandler;
+}  // namespace mojom
+
 // The WebUI handler for chrome://os-settings.
 class OSSettingsUI : public ui::MojoWebUIController {
  public:
@@ -49,6 +53,10 @@ class OSSettingsUI : public ui::MojoWebUIController {
   // passing the pending receiver that will be internally bound.
   void BindInterface(mojo::PendingReceiver<mojom::UserActionRecorder> receiver);
 
+  // Instantiates implementor of the mojom::SearchHandler mojo interface
+  // passing the pending receiver that will be internally bound.
+  void BindInterface(mojo::PendingReceiver<mojom::SearchHandler> receiver);
+
   // Instantiates implementor of the mojom::PageHandlerFactory mojo interface
   // passing the pending receiver that will be internally bound.
   void BindInterface(

chrome/browser/ui/webui/settings/chromeos/search/BUILD.gn

@@ -8,7 +8,10 @@ assert(is_chromeos)
 
 mojom("mojo_bindings") {
   sources = [
+    "search.mojom",
     "search_result_icon.mojom",
     "user_action_recorder.mojom",
   ]
+
+  public_deps = [ "//mojo/public/mojom/base" ]
 }

chrome/browser/ui/webui/settings/chromeos/search/search.mojom

+// 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.
+
+module chromeos.settings.mojom;
+
+import "chrome/browser/ui/webui/settings/chromeos/search/search_result_icon.mojom";
+import "mojo/public/mojom/base/string16.mojom";
+
+// Search result metadata.
+struct SearchResult {
+  // String to be displayed as a result in the UI. Meant to be displayed
+  // directly (i.e., not an ID but rather the actual text).
+  mojo_base.mojom.String16 result_text;
+
+  // The URL path containing the relevant setting, which may or may not contain
+  // URL parameters. For example, the Wi-Fi list settings page is
+  // chrome://os-settings/networks?type=WiFi, so the field would be
+  // "networks?type=WiFi" for this page.
+  string url_path_with_parameters;
+
+  // Icon to display for the search result.
+  SearchResultIcon icon;
+};
+
+// Provides settings search results. Implemented in the browser process;
+// intended to be called from settings JS and Launcher C++.
+interface SearchHandler {
+  // Searches settings for the given query and returns a list of results, sorted
+  // from most relevant to least relevant. An empty array indicates no relevant
+  // results.
+  Search(mojo_base.mojom.String16 query) => (array<SearchResult> results);
+};

chrome/browser/ui/webui/settings/chromeos/search/search_handler.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/ui/webui/settings/chromeos/search/search_handler.h"
+
+#include "base/strings/string_number_conversions.h"
+#include "chrome/browser/ui/webui/settings/chromeos/os_settings_localized_strings_provider.h"
+#include "chrome/browser/ui/webui/settings/chromeos/search/search_concept.h"
+#include "chrome/browser/ui/webui/settings/chromeos/search/search_result_icon.mojom.h"
+#include "chrome/services/local_search_service/public/mojom/types.mojom.h"
+#include "ui/base/l10n/l10n_util.h"
+
+namespace chromeos {
+namespace settings {
+namespace {
+
+const int32_t kLocalSearchServiceMaxLatencyMs = 3000;
+const int32_t kLocalSearchServiceMaxResults = 10;
+
+}  // namespace
+
+// static
+const size_t SearchHandler::kNumMaxResults = 5;
+
+SearchHandler::SearchHandler(
+    OsSettingsLocalizedStringsProvider* strings_provider,
+    local_search_service::mojom::LocalSearchService* local_search_service)
+    : strings_provider_(strings_provider) {
+  DCHECK(strings_provider_);
+  local_search_service->GetIndex(
+      local_search_service::mojom::LocalSearchService::IndexId::CROS_SETTINGS,
+      index_remote_.BindNewPipeAndPassReceiver());
+}
+
+SearchHandler::~SearchHandler() = default;
+
+void SearchHandler::BindInterface(
+    mojo::PendingReceiver<mojom::SearchHandler> pending_receiver) {
+  receivers_.Add(this, std::move(pending_receiver));
+}
+
+void SearchHandler::Search(const base::string16& query,
+                           SearchCallback callback) {
+  index_remote_->Find(
+      query, kLocalSearchServiceMaxLatencyMs, kLocalSearchServiceMaxResults,
+      base::BindOnce(&SearchHandler::OnLocalSearchServiceResults,
+                     base::Unretained(this), std::move(callback)));
+}
+
+void SearchHandler::OnLocalSearchServiceResults(
+    SearchCallback callback,
+    local_search_service::mojom::ResponseStatus response_status,
+    base::Optional<std::vector<local_search_service::mojom::ResultPtr>>
+        results) {
+  switch (response_status) {
+    case local_search_service::mojom::ResponseStatus::UNKNOWN_ERROR:
+    case local_search_service::mojom::ResponseStatus::EMPTY_QUERY:
+    case local_search_service::mojom::ResponseStatus::EMPTY_INDEX:
+      LOG(ERROR) << "Cannot search; LocalSearchService returned "
+                 << response_status << ". Returning empty results array.";
+      std::move(callback).Run({});
+      return;
+    case local_search_service::mojom::ResponseStatus::SUCCESS:
+      DCHECK(results);
+      ReturnSuccessfulResults(std::move(callback), std::move(results));
+      return;
+  }
+
+  NOTREACHED() << "Invalid response status: " << response_status << ".";
+}
+
+void SearchHandler::ReturnSuccessfulResults(
+    SearchCallback callback,
+    base::Optional<std::vector<local_search_service::mojom::ResultPtr>>
+        results) {
+  std::vector<mojom::SearchResultPtr> search_results;
+  for (const auto& result : *results) {
+    mojom::SearchResultPtr result_ptr = ResultToSearchResult(*result);
+    if (result_ptr)
+      search_results.push_back(std::move(result_ptr));
+
+    // Limit the number of results to return.
+    if (search_results.size() == kNumMaxResults)
+      break;
+  }
+
+  std::move(callback).Run(std::move(search_results));
+}
+
+mojom::SearchResultPtr SearchHandler::ResultToSearchResult(
+    const local_search_service::mojom::Result& result) {
+  int message_id;
+
+  // The result's ID is expected to be a stringified int.
+  if (!base::StringToInt(result.id, &message_id))
+    return nullptr;
+
+  const SearchConcept* concept =
+      strings_provider_->GetCanonicalTagMetadata(message_id);
+
+  // If the concept was not registered, no metadata is available. This can occur
+  // if the search tag was dynamically unregistered during the asynchronous
+  // Find() call.
+  if (!concept)
+    return nullptr;
+
+  return mojom::SearchResult::New(l10n_util::GetStringUTF16(message_id),
+                                  concept->url_path_with_parameters,
+                                  concept->icon);
+}
+
+void SearchHandler::Shutdown() {
+  strings_provider_ = nullptr;
+  receivers_.Clear();
+  index_remote_.reset();
+}
+
+}  // namespace settings
+}  // namespace chromeos

chrome/browser/ui/webui/settings/chromeos/search/search_handler.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_UI_WEBUI_SETTINGS_CHROMEOS_SEARCH_SEARCH_HANDLER_H_
+#define CHROME_BROWSER_UI_WEBUI_SETTINGS_CHROMEOS_SEARCH_SEARCH_HANDLER_H_
+
+#include <vector>
+
+#include "base/optional.h"
+#include "chrome/browser/ui/webui/settings/chromeos/search/search.mojom.h"
+#include "chrome/services/local_search_service/public/mojom/local_search_service.mojom.h"
+#include "components/keyed_service/core/keyed_service.h"
+#include "mojo/public/cpp/bindings/pending_receiver.h"
+#include "mojo/public/cpp/bindings/receiver_set.h"
+#include "mojo/public/cpp/bindings/remote.h"
+
+namespace chromeos {
+namespace settings {
+
+class OsSettingsLocalizedStringsProvider;
+
+// Handles search queries for Chrome OS settings. Search() is expected to be
+// invoked by the settings UI as well as the the Launcher search UI. Search
+// results are obtained by matching the provided query against search tags
+// indexed in the LocalSearchService and cross-referencing results with
+// OsSettingsLocalizedStringsProvider.
+//
+// SearchHandler returns at most |kNumMaxResults| results; searches which do not
+// provide any matches result in an empty results array.
+class SearchHandler : public mojom::SearchHandler, public KeyedService {
+ public:
+  // Maximum number of results returned by a Search() call.
+  static const size_t kNumMaxResults;
+
+  SearchHandler(
+      OsSettingsLocalizedStringsProvider* strings_provider,
+      local_search_service::mojom::LocalSearchService* local_search_service);
+  ~SearchHandler() override;
+
+  SearchHandler(const SearchHandler& other) = delete;
+  SearchHandler& operator=(const SearchHandler& other) = delete;
+
+  void BindInterface(
+      mojo::PendingReceiver<mojom::SearchHandler> pending_receiver);
+
+  // mojom::SearchHandler:
+  void Search(const base::string16& query, SearchCallback callback) override;
+
+ private:
+  // KeyedService:
+  void Shutdown() override;
+
+  void OnLocalSearchServiceResults(
+      SearchCallback callback,
+      local_search_service::mojom::ResponseStatus response_status,
+      base::Optional<std::vector<local_search_service::mojom::ResultPtr>>
+          results);
+  void ReturnSuccessfulResults(
+      SearchCallback callback,
+      base::Optional<std::vector<local_search_service::mojom::ResultPtr>>
+          results);
+  mojom::SearchResultPtr ResultToSearchResult(
+      const local_search_service::mojom::Result& result);
+
+  OsSettingsLocalizedStringsProvider* strings_provider_;
+  // Note: Expected to have multiple clients, so a ReceiverSet is used.
+  mojo::ReceiverSet<mojom::SearchHandler> receivers_;
+  mojo::Remote<local_search_service::mojom::Index> index_remote_;
+};
+
+}  // namespace settings
+}  // namespace chromeos
+
+#endif  // CHROME_BROWSER_UI_WEBUI_SETTINGS_CHROMEOS_SEARCH_SEARCH_HANDLER_H_

chrome/browser/ui/webui/settings/chromeos/search/search_handler_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/ui/webui/settings/chromeos/search/search_handler_factory.h"
+
+#include "chrome/browser/local_search_service/local_search_service_proxy.h"
+#include "chrome/browser/local_search_service/local_search_service_proxy_factory.h"
+#include "chrome/browser/profiles/incognito_helpers.h"
+#include "chrome/browser/profiles/profile.h"
+#include "chrome/browser/ui/webui/settings/chromeos/os_settings_localized_strings_provider_factory.h"
+#include "chrome/browser/ui/webui/settings/chromeos/search/search_handler.h"
+#include "components/keyed_service/content/browser_context_dependency_manager.h"
+
+namespace chromeos {
+namespace settings {
+
+// static
+SearchHandler* SearchHandlerFactory::GetForProfile(Profile* profile) {
+  return static_cast<SearchHandler*>(
+      SearchHandlerFactory::GetInstance()->GetServiceForBrowserContext(
+          profile, /*create=*/true));
+}
+
+// static
+SearchHandlerFactory* SearchHandlerFactory::GetInstance() {
+  return base::Singleton<SearchHandlerFactory>::get();
+}
+
+SearchHandlerFactory::SearchHandlerFactory()
+    : BrowserContextKeyedServiceFactory(
+          "SearchHandler",
+          BrowserContextDependencyManager::GetInstance()) {
+  DependsOn(
+      local_search_service::LocalSearchServiceProxyFactory::GetInstance());
+  DependsOn(OsSettingsLocalizedStringsProviderFactory::GetInstance());
+}
+
+SearchHandlerFactory::~SearchHandlerFactory() = default;
+
+KeyedService* SearchHandlerFactory::BuildServiceInstanceFor(
+    content::BrowserContext* context) const {
+  Profile* profile = Profile::FromBrowserContext(context);
+  return new SearchHandler(
+      OsSettingsLocalizedStringsProviderFactory::GetForProfile(profile),
+      local_search_service::LocalSearchServiceProxyFactory::GetForProfile(
+          Profile::FromBrowserContext(profile))
+          ->GetLocalSearchService());
+}
+
+bool SearchHandlerFactory::ServiceIsNULLWhileTesting() const {
+  return true;
+}
+
+content::BrowserContext* SearchHandlerFactory::GetBrowserContextToUse(
+    content::BrowserContext* context) const {
+  return chrome::GetBrowserContextOwnInstanceInIncognito(context);
+}
+
+}  // namespace settings
+}  // namespace chromeos

chrome/browser/ui/webui/settings/chromeos/search/search_handler_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_UI_WEBUI_SETTINGS_CHROMEOS_SEARCH_SEARCH_HANDLER_FACTORY_H_
+#define CHROME_BROWSER_UI_WEBUI_SETTINGS_CHROMEOS_SEARCH_SEARCH_HANDLER_FACTORY_H_
+
+#include "base/memory/singleton.h"
+#include "components/keyed_service/content/browser_context_keyed_service_factory.h"
+
+class Profile;
+
+namespace chromeos {
+namespace settings {
+
+class SearchHandler;
+
+// Factory for SearchHandler; available for incognito and multi-profile cases to
+// support settings search in those contexts.
+class SearchHandlerFactory : public BrowserContextKeyedServiceFactory {
+ public:
+  static SearchHandler* GetForProfile(Profile* profile);
+  static SearchHandlerFactory* GetInstance();
+
+ private:
+  friend struct base::DefaultSingletonTraits<SearchHandlerFactory>;
+
+  SearchHandlerFactory();
+  ~SearchHandlerFactory() override;
+
+  SearchHandlerFactory(const SearchHandlerFactory&) = delete;
+  SearchHandlerFactory& operator=(const SearchHandlerFactory&) = delete;
+
+  // BrowserContextKeyedServiceFactory:
+  KeyedService* BuildServiceInstanceFor(
+      content::BrowserContext* context) const override;
+  bool ServiceIsNULLWhileTesting() const override;
+  content::BrowserContext* GetBrowserContextToUse(
+      content::BrowserContext* context) const override;
+};
+
+}  // namespace settings
+}  // namespace chromeos
+
+#endif  // CHROME_BROWSER_UI_WEBUI_SETTINGS_CHROMEOS_SEARCH_SEARCH_HANDLER_FACTORY_H_

chrome/browser/ui/webui/settings/chromeos/search/search_handler_unittest.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/ui/webui/settings/chromeos/search/search_handler.h"
+
+#include "base/run_loop.h"
+#include "base/strings/utf_string_conversions.h"
+#include "chrome/browser/ui/webui/settings/chromeos/os_settings_localized_strings_provider.h"
+#include "chrome/browser/ui/webui/settings/chromeos/search/search.mojom-test-utils.h"
+#include "chrome/common/webui_url_constants.h"
+#include "chrome/services/local_search_service/local_search_service_impl.h"
+#include "chrome/test/base/testing_browser_process.h"
+#include "chrome/test/base/testing_profile.h"
+#include "chrome/test/base/testing_profile_manager.h"
+#include "chromeos/services/network_config/public/cpp/cros_network_config_test_helper.h"
+#include "content/public/test/browser_task_environment.h"
+#include "mojo/public/cpp/bindings/remote.h"
+#include "testing/gtest/include/gtest/gtest.h"
+
+namespace chromeos {
+namespace settings {
+
+class SearchHandlerTest : public testing::Test {
+ protected:
+  SearchHandlerTest() : profile_manager_(TestingBrowserProcess::GetGlobal()) {}
+  ~SearchHandlerTest() override = default;
+
+  // testing::Test:
+  void SetUp() override {
+    ASSERT_TRUE(profile_manager_.SetUp());
+
+    provider_ = std::make_unique<OsSettingsLocalizedStringsProvider>(
+        profile_manager_.CreateTestingProfile("TestingProfile"),
+        &local_search_service_);
+
+    handler_ = std::make_unique<SearchHandler>(provider_.get(),
+                                               &local_search_service_);
+    handler_->BindInterface(handler_remote_.BindNewPipeAndPassReceiver());
+
+    // Allow asynchronous networking code to complete; specifically, let code
+    // which adds Wi-Fi to the system run so that Wi-Fi search tags can be
+    // queried below.
+    base::RunLoop().RunUntilIdle();
+  }
+
+  content::BrowserTaskEnvironment task_environment_;
+  TestingProfileManager profile_manager_;
+  chromeos::network_config::CrosNetworkConfigTestHelper network_config_helper_;
+  mojo::Remote<mojom::SearchHandler> handler_remote_;
+  local_search_service::LocalSearchServiceImpl local_search_service_;
+  std::unique_ptr<OsSettingsLocalizedStringsProvider> provider_;
+  std::unique_ptr<SearchHandler> handler_;
+};
+
+TEST_F(SearchHandlerTest, Success) {
+  // Search for "Wi-Fi".
+  std::vector<mojom::SearchResultPtr> search_results;
+  mojom::SearchHandlerAsyncWaiter(handler_remote_.get())
+      .Search(base::ASCIIToUTF16("Wi-Fi"), &search_results);
+
+  // Multiple results should be available, and they should have Wi-Fi metadata.
+  EXPECT_GT(search_results.size(), 0u);
+  for (const auto& result : search_results) {
+    EXPECT_EQ(chrome::kWiFiSettingsSubPage, result->url_path_with_parameters);
+    EXPECT_EQ(mojom::SearchResultIcon::kWifi, result->icon);
+  }
+}
+
+TEST_F(SearchHandlerTest, NoResults) {
+  std::vector<mojom::SearchResultPtr> search_results;
+  mojom::SearchHandlerAsyncWaiter(handler_remote_.get())
+      .Search(base::ASCIIToUTF16("QueryWithNoResults"), &search_results);
+  EXPECT_TRUE(search_results.empty());
+}
+
+}  // namespace settings
+}  // namespace chromeos

chrome/browser/ui/webui/settings/chromeos/search/user_action_recorder.mojom

@@ -4,7 +4,8 @@
 
 module chromeos.settings.mojom;
 
-// Records user actions within OS settings.
+// Records user actions within OS settings. Implemented in the browser process;
+// intended to be called from settings JS.
 interface UserActionRecorder {
   // Records that the settings window has been focused.
   RecordPageFocus();

chrome/services/local_search_service/public/mojom/local_search_service.mojom

@@ -10,7 +10,7 @@ import "mojo/public/mojom/base/string16.mojom";
 // LocalSearchService will run as a singleton service so that clients
 // can request Indices from it. LocalSearchService will be responsible for
 // creating Indices, but data update will be the responsibility of
-// clients.
+// clients. Runs in the browser process as a KeyedService.
 interface LocalSearchService {
   // Identifies a globally unique Index of related search data.
   enum IndexId {