Add null check and logs for around device active use case.

In a small subset of devices, we are seeing the device active use case
not being defined. This CL adds a layer of validation to ensure its
definition before use.

BUG=chromium:1405615

(cherry picked from commit ac62487)

Change-Id: I0f9becc25cea976aaef0a34681947e1527d6b3e1
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/4144369
Reviewed-by: Xiyuan Xia <xiyuan@chromium.org>
Commit-Queue: Hirthanan Subenderan <hirthanan@google.com>
Cr-Original-Commit-Position: refs/heads/main@{#1090443}
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/4148927
Auto-Submit: Hirthanan Subenderan <hirthanan@google.com>
Commit-Queue: Rubber Stamper <rubber-stamper@appspot.gserviceaccount.com>
Bot-Commit: Rubber Stamper <rubber-stamper@appspot.gserviceaccount.com>
Cr-Commit-Position: refs/branch-heads/5481@{#188}
Cr-Branched-From: 130f3e4-refs/heads/main@{#1084008}

chromeos/ash/components/device_activity/device_active_use_case.cc

@@ -40,6 +40,7 @@ DeviceActiveUseCase::DeviceActiveUseCase(
       statistics_provider_(
           chromeos::system::StatisticsProvider::GetInstance()) {
   DCHECK(psm_delegate_);
+  DCHECK(local_state_);
 }
 
 DeviceActiveUseCase::~DeviceActiveUseCase() = default;

chromeos/ash/components/device_activity/device_activity_client.cc

@@ -428,10 +428,17 @@ void DeviceActivityClient::OnGetLastPingDatesStatusFetched(
               GetUseCasePtr(psm_rlwe::RlweUseCase::CROS_FRESNEL_FIRST_ACTIVE);
           break;
         default:
-          VLOG(1) << "PSM use case is not supported yet.";
+          LOG(ERROR) << "PSM use case is not supported yet.";
           continue;
       }
 
+      // Crashes may occur due to device_active_use_case_ptr not being defined
+      // at this point.
+      if (device_active_use_case_ptr == nullptr) {
+        LOG(ERROR) << "Device active use case is not defined.";
+        return;
+      }
+
       if (!device_active_use_case_ptr->IsLastKnownPingTimestampSet()) {
         RecordPreservedFileState(
             DeviceActivityClient::PreservedFileState::kReadOkLocalStateEmpty);

chromeos/ash/components/device_activity/device_activity_controller.cc

@@ -168,6 +168,7 @@ DeviceActivityController::DeviceActivityController(
       DeviceActivityClient::DeviceActivityMethod::
           kDeviceActivityControllerConstructor);
 
+  DCHECK(local_state);
   DCHECK(!g_ash_device_activity_controller);
   g_ash_device_activity_controller = this;