Start the migration of passwords from the Keychain.

chrome/browser/password_manager/password_store_proxy_mac.cc

Index: chrome/browser/password_manager/password_store_proxy_mac.cc
diff --git a/chrome/browser/password_manager/password_store_proxy_mac.cc b/chrome/browser/password_manager/password_store_proxy_mac.cc
index 2d16b7ecfef43b1104d789ce34c678d0ad4f26a1..27aed505a4afe537243beeafca419945a2b69559 100644
--- a/chrome/browser/password_manager/password_store_proxy_mac.cc
+++ b/chrome/browser/password_manager/password_store_proxy_mac.cc
@@ -4,8 +4,10 @@
 
 #include "chrome/browser/password_manager/password_store_proxy_mac.h"
 
+#include "base/metrics/histogram_macros.h"
 #include "chrome/browser/password_manager/password_store_mac.h"
 #include "chrome/browser/password_manager/simple_password_store_mac.h"
+#include "components/password_manager/core/common/password_manager_pref_names.h"
 #include "content/public/browser/browser_thread.h"
 #include "crypto/apple_keychain.h"
 
@@ -14,13 +16,23 @@ using password_manager::PasswordStoreChangeList;
 PasswordStoreProxyMac::PasswordStoreProxyMac(
     scoped_refptr<base::SingleThreadTaskRunner> main_thread_runner,
     scoped_ptr<crypto::AppleKeychain> keychain,
-    scoped_ptr<password_manager::LoginDatabase> login_db)
+    scoped_ptr<password_manager::LoginDatabase> login_db,
+    PrefService* prefs)
     : PasswordStore(main_thread_runner, nullptr),
-      login_metadata_db_(login_db.Pass()) {
+      login_metadata_db_(login_db.Pass()),
+      migration_completion_(true, false) {
   DCHECK(login_metadata_db_);
-  // TODO(vasilii): for now the class is just a wrapper around PasswordStoreMac.
-  password_store_mac_ =
-      new PasswordStoreMac(main_thread_runner, nullptr, keychain.Pass());
+  migration_status_.Init(password_manager::prefs::kKeychainMigrationStatus,
+                         prefs);
+  if (migration_status_.GetValue() == MIGRATED) {
+    // The login database will be set later after initialization.
+    password_store_simple_ = new SimplePasswordStoreMac(
+        main_thread_runner, nullptr,
+        scoped_ptr<password_manager::LoginDatabase>());

[vabr (Chromium), 2015/07/03 08:40:48]

optional: I believe nullptr should work here as well. But if you want to keep
the more verbose empty scoped_ptr, because it makes it clear that it is a null
database pointer, that's fine as well.

[vasilii, 2015/07/03 12:59:11]

Done.

+  } else {
+    password_store_mac_ =
+        new PasswordStoreMac(main_thread_runner, nullptr, keychain.Pass());
+  }
 }
 
 PasswordStoreProxyMac::~PasswordStoreProxyMac() {
@@ -37,15 +49,20 @@ bool PasswordStoreProxyMac::Init(
     return false;
   }
 
-  ScheduleTask(
-      base::Bind(&PasswordStoreProxyMac::InitOnBackgroundThread, this));
-  password_store_mac_->InitWithTaskRunner(GetBackgroundTaskRunner());
-  return password_manager::PasswordStore::Init(flare);
+  if (!password_manager::PasswordStore::Init(flare))
+    return false;
+
+  return ScheduleTask(
+      base::Bind(&PasswordStoreProxyMac::InitOnBackgroundThread, this,
+                 static_cast<MigrationStatus>(migration_status_.GetValue())));
 }
 
 void PasswordStoreProxyMac::Shutdown() {
   DCHECK_CURRENTLY_ON(content::BrowserThread::UI);
   PasswordStore::Shutdown();
+  // Wait for InitOnBackgroundThread completion so GetBackend() returns a
+  // correct pointer.
+  migration_completion_.Wait();
   GetBackend()->Shutdown();
   thread_->Stop();
 }
@@ -61,15 +78,55 @@ password_manager::PasswordStore* PasswordStoreProxyMac::GetBackend() const {
   return password_store_simple_.get();
 }
 
-void PasswordStoreProxyMac::InitOnBackgroundThread() {
+void PasswordStoreProxyMac::InitOnBackgroundThread(MigrationStatus status) {
   DCHECK(GetBackgroundTaskRunner()->BelongsToCurrentThread());
   if (!login_metadata_db_->Init()) {
     login_metadata_db_.reset();
     LOG(ERROR) << "Could not create/open login database.";
-    return;
   }
-  if (password_store_mac_)
+
+  if (status == MIGRATED) {
+    password_store_simple_->InitWithTaskRunner(GetBackgroundTaskRunner(),
+                                               login_metadata_db_.Pass());
+  } else {
     password_store_mac_->set_login_metadata_db(login_metadata_db_.get());
+    password_store_mac_->InitWithTaskRunner(GetBackgroundTaskRunner());
+    if (login_metadata_db_ &&
+        (status == NOT_STARTED || status == FAILED_ONCE)) {
+      // Let's try to migrate the passwords.
+      if (password_store_mac_->ImportFromKeychain() ==
+          PasswordStoreMac::MIGRATION_OK) {
+        status = MIGRATED;
+        // Switch from |password_store_mac_| to |password_store_simple_|.
+        password_store_mac_->set_login_metadata_db(nullptr);
+        main_thread_runner_->PostTask(
+            FROM_HERE,
+            base::Bind(&PasswordStoreMac::Shutdown, password_store_mac_));
+        password_store_mac_ = nullptr;
+        password_store_simple_ = new SimplePasswordStoreMac(
+            main_thread_runner_, GetBackgroundTaskRunner(),
+            login_metadata_db_.Pass());
+      } else {
+        status = (status == FAILED_ONCE ? FAILED_TWICE : FAILED_ONCE);
+      }
+      main_thread_runner_->PostTask(
+          FROM_HERE,
+          base::Bind(&PasswordStoreProxyMac::UpdateStatusPref, this, status));
+    }
+  }
+  migration_completion_.Signal();
+  ReportStatusPref(status);
+  DCHECK(GetBackend());
+}
+
+void PasswordStoreProxyMac::UpdateStatusPref(MigrationStatus status) {
+  migration_status_.SetValue(status);
+}
+
+// static
+void PasswordStoreProxyMac::ReportStatusPref(MigrationStatus status) {
+  UMA_HISTOGRAM_ENUMERATION("PasswordManager.KeychainMigration.Status", status,
+                            NUM_MIGRATION_STATUS);
 }
 
 void PasswordStoreProxyMac::ReportMetricsImpl(