[signin] Add histogram recording wether Dice is enabled at startup.

Bug: 771908
Change-Id: Iac535502e4584c3756712cb49b4afb4608fab925
Reviewed-on: https://chromium-review.googlesource.com/737639Reviewed-by: Robert Kaplow <rkaplow@chromium.org>
Reviewed-by: Mihai Sardarescu <msarda@chromium.org>
Commit-Queue: David Roger <droger@chromium.org>
Cr-Commit-Position: refs/heads/master@{#512501}

components/signin/core/browser/account_reconcilor.cc

@@ -12,6 +12,7 @@
 #include "base/json/json_reader.h"
 #include "base/location.h"
 #include "base/logging.h"
+#include "base/metrics/histogram_macros.h"
 #include "base/single_thread_task_runner.h"
 #include "base/stl_util.h"
 #include "base/strings/string_number_conversions.h"
@@ -94,14 +95,16 @@ AccountReconcilor::AccountReconcilor(
       account_reconcilor_lock_count_(0),
       reconcile_on_unblock_(false) {
   VLOG(1) << "AccountReconcilor::AccountReconcilor";
+  PrefService* prefs = client_->GetPrefs();
   if (ShouldMigrateToDiceOnStartup()) {
-    PrefService* prefs = client_->GetPrefs();
     DCHECK(prefs);
     if (!signin::IsDiceEnabledForProfile(prefs))
       VLOG(1) << "Profile is migrating to Dice";
     signin::MigrateProfileToDice(client->GetPrefs());
     DCHECK(signin::IsDiceEnabledForProfile(prefs));
   }
+  UMA_HISTOGRAM_BOOLEAN("Signin.DiceEnabledForProfile",
+                        signin::IsDiceEnabledForProfile(prefs));
 }
 
 AccountReconcilor::~AccountReconcilor() {

components/signin/ios/browser/account_consistency_service_unittest.mm

@@ -8,6 +8,7 @@
 
 #include <memory>
 
+#include "base/memory/ptr_util.h"
 #include "components/signin/core/browser/account_reconcilor.h"
 #include "components/signin/core/browser/account_tracker_service.h"
 #include "components/signin/core/browser/fake_signin_manager.h"
@@ -76,8 +77,8 @@ class FakeAccountConsistencyService : public AccountConsistencyService {
 // Mock AccountReconcilor to catch call to OnReceivedManageAccountsResponse.
 class MockAccountReconcilor : public AccountReconcilor {
  public:
-  MockAccountReconcilor()
-      : AccountReconcilor(nullptr, nullptr, nullptr, nullptr) {}
+  MockAccountReconcilor(SigninClient* client)
+      : AccountReconcilor(nullptr, nullptr, client, nullptr) {}
   MOCK_METHOD1(OnReceivedManageAccountsResponse, void(signin::GAIAServiceType));
 };
 
@@ -148,6 +149,8 @@ class AccountConsistencyServiceTest : public PlatformTest {
         false /* store_last_modified */);
     cookie_settings_ =
         new content_settings::CookieSettings(settings_map_.get(), &prefs_, "");
+    account_reconcilor_ =
+        base::MakeUnique<MockAccountReconcilor>(signin_client_.get());
     ResetAccountConsistencyService();
   }
 
@@ -184,7 +187,7 @@ class AccountConsistencyServiceTest : public PlatformTest {
       account_consistency_service_->Shutdown();
     }
     account_consistency_service_.reset(new FakeAccountConsistencyService(
-        &browser_state_, &account_reconcilor_, cookie_settings_,
+        &browser_state_, account_reconcilor_.get(), cookie_settings_,
         gaia_cookie_manager_service_.get(), signin_client_.get(),
         signin_manager_.get()));
   }
@@ -237,7 +240,6 @@ class AccountConsistencyServiceTest : public PlatformTest {
   // Creates test threads, necessary for ActiveStateManager that needs a UI
   // thread.
   web::TestWebThreadBundle thread_bundle_;
-  MockAccountReconcilor account_reconcilor_;
   AccountTrackerService account_tracker_service_;
   web::TestBrowserState browser_state_;
   sync_preferences::TestingPrefServiceSyncable prefs_;
@@ -248,6 +250,7 @@ class AccountConsistencyServiceTest : public PlatformTest {
   std::unique_ptr<TestSigninClient> signin_client_;
   std::unique_ptr<FakeSigninManager> signin_manager_;
   std::unique_ptr<MockGaiaCookieManagerService> gaia_cookie_manager_service_;
+  std::unique_ptr<MockAccountReconcilor> account_reconcilor_;
   scoped_refptr<HostContentSettingsMap> settings_map_;
   scoped_refptr<content_settings::CookieSettings> cookie_settings_;
   bool remove_cookie_callback_called_;
@@ -388,8 +391,8 @@ TEST_F(AccountConsistencyServiceTest, ChromeManageAccountsDefault) {
        HTTPVersion:@"HTTP/1.1"
       headerFields:headers];
   account_consistency_service_->SetWebStateHandler(&web_state_, delegate);
-  EXPECT_CALL(account_reconcilor_, OnReceivedManageAccountsResponse(
-                                       signin::GAIA_SERVICE_TYPE_DEFAULT))
+  EXPECT_CALL(*account_reconcilor_, OnReceivedManageAccountsResponse(
+                                        signin::GAIA_SERVICE_TYPE_DEFAULT))
       .Times(1);
   EXPECT_FALSE(
       web_state_.ShouldAllowResponse(response, /* for_main_frame = */ true));

tools/metrics/histograms/histograms.xml

@@ -77976,6 +77976,13 @@ http://cs/file:chrome/histograms.xml - but prefer this file for new entries.
   <summary>The total number of accounts in the cookie jar.</summary>
 </histogram>
 
+<histogram name="Signin.DiceEnabledForProfile" enum="Boolean">
+  <owner>droger@chromium.org</owner>
+  <summary>
+    Whether Dice is enabled for the current profile, recorded at startup.
+  </summary>
+</histogram>
+
 <histogram name="Signin.DiceResponseHeader" enum="SigninDiceResponseHeader">
   <owner>droger@chromium.org</owner>
   <summary>Records Dice responses (signin and signout).</summary>