[SmartLock] Remove outdated and incorrect test hacks in test.

Also only Initialize the EasyUnlockService in the test once the test
Profile object is ready.

This change is high-priority because without it, the fix for
crbug.com/953027 causes this test to fail (the incomplete Profile
caused DCHECKs in known_user.h to fail).

Bug: 857494, 953027
Change-Id: I5a389b3017e6428136295ccd6899ffc05c6c354b
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1669762
Commit-Queue: Ryan Hansberry <hansberry@chromium.org>
Reviewed-by: Kyle Horimoto <khorimoto@chromium.org>
Cr-Commit-Position: refs/heads/master@{#672096}

chrome/browser/chromeos/login/easy_unlock/easy_unlock_service_regular.cc

@@ -295,10 +295,10 @@ AccountId EasyUnlockServiceRegular::GetAccountId() const {
   DCHECK(identity_manager);
   const CoreAccountInfo account_info =
       identity_manager->GetPrimaryAccountInfo();
+
   // A regular signed-in (i.e., non-login) profile should always have an email.
-  // TODO(crbug.com/857494): Enable this DCHECK once all browser tests create
-  // correctly signed in profiles.
-  // DCHECK(!account_info.email.empty());
+  DCHECK(!account_info.email.empty());
+
   return AccountIdFromAccountInfo(account_info);
 }
 
@@ -364,18 +364,17 @@ void EasyUnlockServiceRegular::InitializeInternal() {
   pref_manager_.reset(new proximity_auth::ProximityAuthProfilePrefManager(
       profile()->GetPrefs(), multidevice_setup_client_));
 
-  // TODO(tengs): Due to badly configured browser_tests, Chrome crashes during
-  // shutdown. Revisit this condition after migration is fully completed.
+  // TODO(crbug.com/857494): Thousands of unrelated browser_tests provide a
+  // profile with an empty email to this service, causing crashes further on.
+  // Investigate what this service is doing so differently (i.e., incorrectly)
+  // from others that causes such issues with so many browser_tests.
   if (!base::CommandLine::ForCurrentProcess()->HasSwitch(switches::kTestType)) {
-    // Note: There is no local state in tests.
-    if (g_browser_process->local_state()) {
-      pref_manager_->StartSyncingToLocalState(g_browser_process->local_state(),
-                                              GetAccountId());
-    }
-
-    LoadRemoteDevices();
+    pref_manager_->StartSyncingToLocalState(g_browser_process->local_state(),
+                                            GetAccountId());
   }
 
+  LoadRemoteDevices();
+
   registrar_.Init(profile()->GetPrefs());
   registrar_.Add(
       proximity_auth::prefs::kProximityAuthIsChromeOSLoginEnabled,
@@ -394,6 +393,8 @@ void EasyUnlockServiceRegular::ShutdownInternal() {
   device_sync_client_->RemoveObserver(this);
 
   multidevice_setup_client_->RemoveObserver(this);
+
+  weak_ptr_factory_.InvalidateWeakPtrs();
 }
 
 bool EasyUnlockServiceRegular::IsAllowedInternal() const {

chrome/browser/chromeos/login/easy_unlock/easy_unlock_service_unittest_chromeos.cc

@@ -83,14 +83,10 @@ GetDefaultMultiDeviceSetupClient() {
 // EasyUnlockService factory function injected into testing profiles.
 std::unique_ptr<KeyedService> CreateEasyUnlockServiceForTest(
     content::BrowserContext* context) {
-  std::unique_ptr<EasyUnlockServiceRegular> service(
-      new EasyUnlockServiceRegular(
-          Profile::FromBrowserContext(context),
-          nullptr /* secure_channel_client */,
-          std::make_unique<MockEasyUnlockNotificationController>(),
-          GetDefaultDeviceSyncClient(), GetDefaultMultiDeviceSetupClient()));
-  service->Initialize();
-  return std::move(service);
+  return std::make_unique<EasyUnlockServiceRegular>(
+      Profile::FromBrowserContext(context), nullptr /* secure_channel_client */,
+      std::make_unique<MockEasyUnlockNotificationController>(),
+      GetDefaultDeviceSyncClient(), GetDefaultMultiDeviceSetupClient());
 }
 
 }  // namespace
@@ -165,6 +161,10 @@ class EasyUnlockServiceTest : public testing::Test {
         AccountId::FromUserEmailGaiaId(email, *gaia_id));
     profile.get()->set_profile_name(email);
 
+    // Only initialize the service once the profile is completely ready. If done
+    // earlier, indirect usage of user_manager::KnownUser would crash.
+    EasyUnlockService::Get(profile.get())->Initialize();
+
     return profile;
   }