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: I47029452e7ba945171090d9fe9de065e5c0da83c
Reviewed-on: https://chromium-review.googlesource.com/c/1470754
Auto-Submit: Sylvain Defresne <sdefresne@chromium.org>
Reviewed-by: David Roger <droger@chromium.org>
Commit-Queue: David Roger <droger@chromium.org>
Cr-Commit-Position: refs/heads/master@{#631798}
diff --git a/ios/chrome/browser/browser_state/chrome_browser_state_manager_impl.cc b/ios/chrome/browser/browser_state/chrome_browser_state_manager_impl.cc
index c64c504..0064f15 100644
--- a/ios/chrome/browser/browser_state/chrome_browser_state_manager_impl.cc
+++ b/ios/chrome/browser/browser_state/chrome_browser_state_manager_impl.cc
@@ -226,7 +226,7 @@
 
   identity::IdentityManager* identity_manager =
       IdentityManagerFactory::GetForBrowserState(browser_state);
-  AccountInfo account_info = identity_manager->GetPrimaryAccountInfo();
+  CoreAccountInfo account_info = identity_manager->GetPrimaryAccountInfo();
   base::string16 username = base::UTF8ToUTF16(account_info.email);
 
   size_t browser_state_index =