arc: Restore broken auth code requst on demand.

chrome/browser/chromeos/arc/arc_auth_service.h

Index: chrome/browser/chromeos/arc/arc_auth_service.h
diff --git a/chrome/browser/chromeos/arc/arc_auth_service.h b/chrome/browser/chromeos/arc/arc_auth_service.h
index bef5aa4e5efa8cf99c916533e37d3298433c0b8f..deb47563a21e3a1e52d5d37cf44ae9331475a42f 100644
--- a/chrome/browser/chromeos/arc/arc_auth_service.h
+++ b/chrome/browser/chromeos/arc/arc_auth_service.h
@@ -205,7 +205,7 @@ class ArcAuthService : public ArcService,
   UIPage ui_page() const { return ui_page_; }
 
   // Returns current page status, relevant to the specific page.
-  const base::string16& ui_page_status() { return ui_page_status_; }
+  const base::string16& ui_page_status() const { return ui_page_status_; }
 
  private:
   void StartArc();
@@ -223,6 +223,7 @@ class ArcAuthService : public ArcService,
   void StartArcIfSignedIn();
   void OnArcDataRemoved(bool success);
   void OnArcSignInTimeout();
+  bool IsAuthCodeRequest() const;
 
   // Unowned pointer. Keeps current profile.
   Profile* profile_ = nullptr;