SyncAuthManager: Expose static DetermineAccountToUse

This will be used by some autofill metrics.

Bug: 903290
Change-Id: I40df75f93a3b25d1beb2ba77cb231a227b44c8ab
Reviewed-on: https://chromium-review.googlesource.com/c/1350984Reviewed-by: Sebastien Seguin-Gagnon <sebsg@chromium.org>
Commit-Queue: Marc Treib <treib@chromium.org>
Cr-Commit-Position: refs/heads/master@{#611116}

components/browser_sync/sync_auth_manager.cc

@@ -351,27 +351,25 @@ void SyncAuthManager::ResetRequestAccessTokenBackoffForTest() {
   request_access_token_backoff_.Reset();
 }
 
-SyncAuthManager::SyncAccountInfo SyncAuthManager::DetermineAccountToUse()
-    const {
-  DCHECK(registered_for_auth_notifications_);
-
+// static
+SyncAuthManager::SyncAccountInfo SyncAuthManager::DetermineAccountToUse(
+    identity::IdentityManager* identity_manager,
+    bool allow_secondary_accounts) {
   // If there is a "primary account", i.e. the user explicitly chose to
   // sign-in to Chrome, then always use that account.
-  if (identity_manager_->HasPrimaryAccount()) {
-    return SyncAccountInfo(identity_manager_->GetPrimaryAccountInfo(),
+  if (identity_manager->HasPrimaryAccount()) {
+    return SyncAccountInfo(identity_manager->GetPrimaryAccountInfo(),
                            /*is_primary=*/true);
   }
 
   // Otherwise, fall back to the default content area signed-in account.
-  // TODO(crbug.com/871221): Add tests for this code path.
-  if (base::FeatureList::IsEnabled(switches::kSyncStandaloneTransport) &&
-      base::FeatureList::IsEnabled(switches::kSyncSupportSecondaryAccount)) {
+  if (allow_secondary_accounts) {
     // Check if there is a content area signed-in account, and we have a refresh
     // token for it.
     std::vector<AccountInfo> cookie_accounts =
-        identity_manager_->GetAccountsInCookieJar();
+        identity_manager->GetAccountsInCookieJar();
     if (!cookie_accounts.empty() &&
-        identity_manager_->HasAccountWithRefreshToken(
+        identity_manager->HasAccountWithRefreshToken(
             cookie_accounts[0].account_id)) {
       return SyncAccountInfo(cookie_accounts[0], /*is_primary=*/false);
     }
@@ -379,6 +377,15 @@ SyncAuthManager::SyncAccountInfo SyncAuthManager::DetermineAccountToUse()
   return SyncAccountInfo();
 }
 
+SyncAuthManager::SyncAccountInfo SyncAuthManager::DetermineAccountToUse()
+    const {
+  DCHECK(registered_for_auth_notifications_);
+  return DetermineAccountToUse(
+      identity_manager_,
+      base::FeatureList::IsEnabled(switches::kSyncStandaloneTransport) &&
+          base::FeatureList::IsEnabled(switches::kSyncSupportSecondaryAccount));
+}
+
 bool SyncAuthManager::UpdateSyncAccountIfNecessary() {
   SyncAccountInfo new_account = DetermineAccountToUse();
   // If we're already using this account and its |is_primary| bit hasn't changed

components/browser_sync/sync_auth_manager.h

@@ -109,9 +109,14 @@ class SyncAuthManager : public identity::IdentityManager::Observer {
   bool IsRetryingAccessTokenFetchForTest() const;
   void ResetRequestAccessTokenBackoffForTest();
 
- private:
   // Determines which account should be used for Sync and returns the
-  // corresponding AccountInfo.
+  // corresponding SyncAccountInfo. This is exposed so that autofill metrics
+  // code can use it.
+  static SyncAccountInfo DetermineAccountToUse(
+      identity::IdentityManager* identity_manager,
+      bool allow_secondary_accounts);
+
+ private:
   SyncAccountInfo DetermineAccountToUse() const;
 
   // Updates |sync_account_| to the appropriate account (i.e.