Turn ArcSupportHost from Observer model to Delegate

chrome/browser/chromeos/arc/auth/arc_manual_auth_code_fetcher.h

Index: chrome/browser/chromeos/arc/auth/arc_manual_auth_code_fetcher.h
diff --git a/chrome/browser/chromeos/arc/auth/arc_manual_auth_code_fetcher.h b/chrome/browser/chromeos/arc/auth/arc_manual_auth_code_fetcher.h
index 7975dccf1d3e021d3f125897b3d369e4063034d9..c8124260a7d9292d55a0a6b434210a20b47760e8 100644
--- a/chrome/browser/chromeos/arc/auth/arc_manual_auth_code_fetcher.h
+++ b/chrome/browser/chromeos/arc/auth/arc_manual_auth_code_fetcher.h
@@ -23,7 +23,7 @@ class ArcAuthContext;
 // Implements the auth token fetching procedure with user's "SIGN IN" button
 // click.
 class ArcManualAuthCodeFetcher : public ArcAuthCodeFetcher,
-                                 public ArcSupportHost::Observer {
+                                 public ArcSupportHost::AuthDelegate {
  public:
   ArcManualAuthCodeFetcher(ArcAuthContext* context,
                            ArcSupportHost* support_host);
@@ -38,10 +38,10 @@ class ArcManualAuthCodeFetcher : public ArcAuthCodeFetcher,
   // Called when HTTP request gets ready.
   void OnContextPrepared(net::URLRequestContextGetter* request_context_getter);
 
-  // ArcSupportHost::Observer:
+  // ArcSupportHost::AuthDelegate:
   void OnAuthSucceeded(const std::string& auth_code) override;
   void OnAuthFailed() override;
-  void OnRetryClicked() override;
+  void OnAuthRetryClicked() override;
 
   ArcAuthContext* const context_;
   ArcSupportHost* const support_host_;