Preparation to convert GetPrimaryAccount to return CoreAccountInfo

Change client code to work as if IdentityManager::GetPrimaryAccount
where returning a CoreAccountInfo instead of an AccountInfo. Method
will be updated in a followup CL.

This CL was uploaded by git cl split.

Bug: 926204
Change-Id: Ic7e29b114fd39ee0c55cafb1a0e526eb1aa78244
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1499559Reviewed-by: Sergio Collazos <sczs@chromium.org>
Commit-Queue: Sylvain Defresne <sdefresne@chromium.org>
Auto-Submit: Sylvain Defresne <sdefresne@chromium.org>
Cr-Commit-Position: refs/heads/master@{#638627}

ios/chrome/browser/ui/settings/google_services/accounts_table_view_controller.mm

@@ -551,10 +551,14 @@ typedef NS_ENUM(NSInteger, ItemType) {
   NSString* continueButtonTitle =
       l10n_util::GetNSString(IDS_IOS_DISCONNECT_DIALOG_CONTINUE_BUTTON_MOBILE);
   if ([self authService] -> IsAuthenticatedIdentityManaged()) {
-    std::string hosted_domain =
-        IdentityManagerFactory::GetForBrowserState(_browserState)
-            ->GetPrimaryAccountInfo()
-            .hosted_domain;
+    identity::IdentityManager* identityManager =
+        IdentityManagerFactory::GetForBrowserState(_browserState);
+    base::Optional<AccountInfo> accountInfo =
+        identityManager->FindExtendedAccountInfoForAccount(
+            identityManager->GetPrimaryAccountInfo());
+    std::string hosted_domain = accountInfo.has_value()
+                                    ? accountInfo.value().hosted_domain
+                                    : std::string();
     if (unified_consent::IsUnifiedConsentFeatureEnabled()) {
       title =
           l10n_util::GetNSString(IDS_IOS_MANAGED_DISCONNECT_DIALOG_TITLE_UNITY);