Replace DeviceType check in smart dim with Flags

Smart dim only works on Chromebook; previously we use DeviceType to
check this, this CL replace it with base::FeatureList.

default on all Chromebook devices

Bug: 994011, 980826
Test: tested in conjunction with CrOS CLs that enable the flag by
Change-Id: I92e685728b173302d21e678051cfc463eaa0d85a
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1757410Reviewed-by: Xiyuan Xia <xiyuan@chromium.org>
Reviewed-by: Andrew Moylan <amoylan@chromium.org>
Commit-Queue: Xinglong Luan <alanlxl@chromium.org>
Cr-Commit-Position: refs/heads/master@{#696678}

chrome/browser/chromeos/dbus/machine_learning_decision_service_provider.cc

@@ -5,8 +5,9 @@
 #include "chrome/browser/chromeos/dbus/machine_learning_decision_service_provider.h"
 
 #include "base/bind.h"
+#include "base/feature_list.h"
 #include "chrome/browser/chromeos/power/ml/user_activity_controller.h"
-#include "chromeos/constants/devicetype.h"
+#include "chrome/common/chrome_features.h"
 #include "dbus/bus.h"
 #include "dbus/message.h"
 #include "third_party/cros_system_api/dbus/service_constants.h"
@@ -47,9 +48,9 @@ void MachineLearningDecisionServiceProvider::ShouldDeferScreenDim(
   std::unique_ptr<dbus::Response> response =
       dbus::Response::FromMethodCall(method_call);
 
-  // Smart dim only works on chromebook devices. Simply return false on other
-  // device types.
-  if (chromeos::GetDeviceType() != chromeos::DeviceType::kChromebook) {
+  // Smart dim only works when features::kSmartDim is enabled. Simply return
+  // false otherwise.
+  if (!base::FeatureList::IsEnabled(features::kSmartDim)) {
     SendSmartDimDecision(std::move(response), std::move(response_sender),
                          false);
     return;

chrome/browser/chromeos/power/ml/user_activity_controller.cc

@@ -4,8 +4,9 @@
 
 #include "chrome/browser/chromeos/power/ml/user_activity_controller.h"
 
+#include "base/feature_list.h"
 #include "chrome/browser/chromeos/login/users/chrome_user_manager.h"
-#include "chromeos/constants/devicetype.h"
+#include "chrome/common/chrome_features.h"
 #include "chromeos/dbus/dbus_thread_manager.h"
 #include "components/session_manager/session_manager_types.h"
 #include "components/viz/host/host_frame_sink_manager.h"
@@ -18,7 +19,7 @@ namespace power {
 namespace ml {
 
 UserActivityController::UserActivityController() {
-  if (chromeos::GetDeviceType() != chromeos::DeviceType::kChromebook)
+  if (!base::FeatureList::IsEnabled(features::kSmartDim))
     return;
 
   chromeos::PowerManagerClient* power_manager_client =

chrome/common/chrome_features.cc

@@ -797,6 +797,9 @@ const base::Feature kCrOSEnableUSMUserService{"CrOSEnableUSMUserService",
 const base::Feature kMachineLearningService{"MachineLearningService",
                                             base::FEATURE_DISABLED_BY_DEFAULT};
 
+// Enables or disables SmartDim on Chrome OS.
+const base::Feature kSmartDim{"SmartDim", base::FEATURE_DISABLED_BY_DEFAULT};
+
 // Enable USBGuard at the lockscreen on Chrome OS.
 // TODO(crbug.com/874630): Remove this kill-switch
 const base::Feature kUsbguard{"USBGuard", base::FEATURE_DISABLED_BY_DEFAULT};

chrome/common/chrome_features.h

@@ -501,6 +501,8 @@ extern const base::Feature kCrOSEnableUSMUserService;
 COMPONENT_EXPORT(CHROME_FEATURES)
 extern const base::Feature kMachineLearningService;
 
+COMPONENT_EXPORT(CHROME_FEATURES) extern const base::Feature kSmartDim;
+
 COMPONENT_EXPORT(CHROME_FEATURES) extern const base::Feature kUsbguard;
 
 COMPONENT_EXPORT(CHROME_FEATURES) extern const base::Feature kUsbbouncer;