Implemented logic to provide feature flags for the Help App.

- For some of the flags, I've extended HelpAppUIDelegate to contain
logic that depends on code in "chrome/".
- Moved existing code to obtain board name, customization id and
version to HelpAppUIDelegate.


Bug: b/140150028
Change-Id: Ie2cbbdacf84692724a69c2b106f703ceadeb7a74
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2073438
Commit-Queue: Callistus Tan <callistus@google.com>
Auto-Submit: Callistus Tan <callistus@google.com>
Reviewed-by: Alexander Alekseev <alemate@chromium.org>
Reviewed-by: Trent Apted <tapted@chromium.org>
Cr-Commit-Position: refs/heads/master@{#748539}

chrome/browser/chromeos/BUILD.gn

@@ -63,6 +63,7 @@ source_set("chromeos") {
     "//apps",
     "//ash",
     "//ash/public/cpp",
+    "//ash/public/mojom",
     "//ash/system/message_center/arc",
     "//build:branding_buildflags",
     "//chrome/app:command_ids",
@@ -220,6 +221,7 @@ source_set("chromeos") {
     "//components/policy/core/common",
     "//components/policy/core/common:common_constants",
     "//components/pref_registry",
+    "//components/prefs",
     "//components/printing/common:mojo_interfaces",
     "//components/proxy_config",
     "//components/quirks",

chrome/browser/chromeos/web_applications/chrome_help_app_ui_delegate.cc

@@ -4,9 +4,21 @@
 
 #include "chrome/browser/chromeos/web_applications/chrome_help_app_ui_delegate.h"
 
+#include "ash/public/cpp/assistant/assistant_state.h"
+#include "ash/public/cpp/tablet_mode.h"
+#include "ash/public/mojom/assistant_state_controller.mojom.h"
+#include "base/system/sys_info.h"
+#include "chrome/browser/chromeos/arc/arc_util.h"
+#include "chrome/browser/chromeos/assistant/assistant_util.h"
+#include "chrome/browser/chromeos/login/quick_unlock/quick_unlock_utils.h"
 #include "chrome/browser/profiles/profile.h"
 #include "chrome/browser/ui/chrome_pages.h"
 #include "chromeos/components/help_app_ui/url_constants.h"
+#include "chromeos/services/multidevice_setup/public/cpp/prefs.h"
+#include "chromeos/system/statistics_provider.h"
+#include "components/prefs/pref_service.h"
+#include "content/public/browser/web_ui_data_source.h"
+#include "ui/events/devices/device_data_manager.h"
 #include "url/gurl.h"
 
 ChromeHelpAppUIDelegate::ChromeHelpAppUIDelegate(content::WebUI* web_ui)
@@ -25,3 +37,47 @@ base::Optional<std::string> ChromeHelpAppUIDelegate::OpenFeedbackDialog() {
       std::string() /* category_tag */, std::string() /* extra_diagnostics */);
   return base::nullopt;
 }
+
+void ChromeHelpAppUIDelegate::PopulateLoadTimeData(
+    content::WebUIDataSource* source) {
+  // Add strings that can be pulled in.
+  source->AddString("boardName", base::SysInfo::GetLsbReleaseBoard());
+  source->AddString("chromeOSVersion", base::SysInfo::OperatingSystemVersion());
+  std::string customization_id;
+  chromeos::system::StatisticsProvider* provider =
+      chromeos::system::StatisticsProvider::GetInstance();
+  // Customization id does not exist for browser tests, but it is fine for this
+  // to be an empty string.
+  provider->GetMachineStatistic(chromeos::system::kCustomizationIdKey,
+                                &customization_id);
+  source->AddString("customizationId", customization_id);
+
+  Profile* profile = Profile::FromWebUI(web_ui_);
+  PrefService* pref_service = profile->GetPrefs();
+
+  // Checks if any of the MultiDevice features (e.g. Instant Tethering,
+  // Messages, Smart Lock) is allowed on this device.
+  source->AddBoolean(
+      "multiDeviceFeaturesAllowed",
+      chromeos::multidevice_setup::AreAnyMultiDeviceFeaturesAllowed(
+          pref_service));
+  source->AddBoolean("tabletMode", ash::TabletMode::Get()->InTabletMode());
+  // Checks if there are active touch screens.
+  source->AddBoolean(
+      "hasTouchScreen",
+      ui::DeviceDataManager::GetInstance()->GetTouchscreenDevices().empty());
+  // Checks if the Google Assistant is allowed on this device by going through
+  // policies.
+  ash::mojom::AssistantAllowedState assistant_allowed_state =
+      assistant::IsAssistantAllowedForProfile(profile);
+  source->AddBoolean(
+      "assistantAllowed",
+      assistant_allowed_state == ash::mojom::AssistantAllowedState::ALLOWED);
+  source->AddBoolean(
+      "assistantEnabled",
+      ash::AssistantState::Get()->settings_enabled().value_or(false));
+  source->AddBoolean("playStoreEnabled",
+                     arc::IsArcPlayStoreEnabledForProfile(profile));
+  source->AddBoolean("pinEnabled",
+                     chromeos::quick_unlock::IsPinEnabled(pref_service));
+}

chrome/browser/chromeos/web_applications/chrome_help_app_ui_delegate.h

@@ -25,6 +25,7 @@ class ChromeHelpAppUIDelegate : public HelpAppUIDelegate {
 
   // HelpAppUIDelegate:
   base::Optional<std::string> OpenFeedbackDialog() override;
+  void PopulateLoadTimeData(content::WebUIDataSource* source) override;
 
  private:
   content::WebUI* web_ui_;  // Owns |this|.

chromeos/components/help_app_ui/help_app_ui.cc

@@ -51,7 +51,8 @@ HelpAppUI::HelpAppUI(content::WebUI* web_ui,
   host_source->OverrideContentSecurityPolicyChildSrc(csp);
 
   content::WebUIDataSource* untrusted_source =
-      CreateHelpAppUntrustedDataSource();
+      CreateHelpAppUntrustedDataSource(delegate_.get());
+
   content::WebUIDataSource::Add(browser_context, untrusted_source);
 
   // Add ability to request chrome-untrusted: URLs.

chromeos/components/help_app_ui/help_app_ui_delegate.h

@@ -9,6 +9,10 @@
 
 #include "base/optional.h"
 
+namespace content {
+class WebUIDataSource;
+}
+
 // A delegate which exposes browser functionality from //chrome to the help app
 // ui page handler.
 class HelpAppUIDelegate {
@@ -19,6 +23,10 @@ class HelpAppUIDelegate {
   // Returns an optional error message if unable to open the dialog or nothing
   // if the dialog was determined to have opened successfully.
   virtual base::Optional<std::string> OpenFeedbackDialog() = 0;
+
+  // Takes a WebUIDataSource, and adds device flags (e.g. board name) and
+  // feature flags (e.g. Google Assistant).
+  virtual void PopulateLoadTimeData(content::WebUIDataSource* source) = 0;
 };
 
 #endif  // CHROMEOS_COMPONENTS_HELP_APP_UI_HELP_APP_UI_DELEGATE_H_

chromeos/components/help_app_ui/help_app_untrusted_ui.cc

@@ -4,19 +4,19 @@
 
 #include "chromeos/components/help_app_ui/help_app_untrusted_ui.h"
 
-#include "base/system/sys_info.h"
+#include "chromeos/components/help_app_ui/help_app_ui_delegate.h"
 #include "chromeos/components/help_app_ui/url_constants.h"
 #include "chromeos/grit/chromeos_help_app_bundle_resources.h"
 #include "chromeos/grit/chromeos_help_app_bundle_resources_map.h"
 #include "chromeos/grit/chromeos_help_app_resources.h"
-#include "chromeos/system/statistics_provider.h"
 #include "content/public/browser/web_ui_data_source.h"
 #include "ui/resources/grit/webui_resources.h"
 
 namespace chromeos {
 
 // static
-content::WebUIDataSource* CreateHelpAppUntrustedDataSource() {
+content::WebUIDataSource* CreateHelpAppUntrustedDataSource(
+    HelpAppUIDelegate* delegate) {
   content::WebUIDataSource* source =
       content::WebUIDataSource::Create(kChromeUIHelpAppUntrustedURL);
   source->AddResourcePath("app.html", IDR_HELP_APP_APP_HTML);
@@ -29,17 +29,10 @@ content::WebUIDataSource* CreateHelpAppUntrustedDataSource() {
                             kChromeosHelpAppBundleResources[i].value);
   }
 
-  // Add strings that can be pulled in.
-  source->AddString("boardName", base::SysInfo::GetLsbReleaseBoard());
-  source->AddString("chromeOSVersion", base::SysInfo::OperatingSystemVersion());
-  std::string customization_id;
-  chromeos::system::StatisticsProvider* provider =
-      chromeos::system::StatisticsProvider::GetInstance();
-  provider->GetMachineStatistic(chromeos::system::kCustomizationIdKey,
-                                &customization_id);
-  source->AddString("customizationId", customization_id);
-  source->UseStringsJs();
+  // Add device and feature flags.
+  delegate->PopulateLoadTimeData(source);
 
+  source->UseStringsJs();
   source->AddFrameAncestor(GURL(kChromeUIHelpAppURL));
   return source;
 }

chromeos/components/help_app_ui/help_app_untrusted_ui.h

@@ -9,9 +9,12 @@ namespace content {
 class WebUIDataSource;
 }
 
+class HelpAppUIDelegate;
+
 namespace chromeos {
 // The data source creation for chrome-untrusted://help-app.
-content::WebUIDataSource* CreateHelpAppUntrustedDataSource();
+content::WebUIDataSource* CreateHelpAppUntrustedDataSource(
+    HelpAppUIDelegate* delegate);
 }  // namespace chromeos
 
 #endif  // CHROMEOS_COMPONENTS_HELP_APP_UI_HELP_APP_UNTRUSTED_UI_H_