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components/ntp_snippets/remote/ntp_snippets_status_service.cc

 // Copyright 2016 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "components/ntp_snippets/remote/ntp_snippets_status_service.h"
 
 #include <string>
 
 #include "components/ntp_snippets/features.h"
 #include "components/ntp_snippets/pref_names.h"
@@ skipping 47 matching lines @@
   // Notify about the current state before registering the observer, to make
   // sure we don't get a double notification due to an undefined start state.
   disabled_reason_ = GetDisabledReasonFromDeps();
   disabled_reason_change_callback_.Run(disabled_reason_);
 
   signin_observer_.Add(signin_manager_);
 
   pref_change_registrar_.Init(pref_service_);
   pref_change_registrar_.Add(
       prefs::kEnableSnippets,
-      base::Bind(&NTPSnippetsStatusService::OnStateChanged,
+      base::Bind(&NTPSnippetsStatusService::OnSnippetsEnabledChanged,
                  base::Unretained(this)));
 }
 
-void NTPSnippetsStatusService::OnStateChanged() {
-  DisabledReason new_disabled_reason = GetDisabledReasonFromDeps();
+void NTPSnippetsStatusService::OnSnippetsEnabledChanged() {
+  OnStateChanged(GetDisabledReasonFromDeps());
+}
 
+void NTPSnippetsStatusService::OnStateChanged(
+    DisabledReason new_disabled_reason) {
   if (new_disabled_reason == disabled_reason_)
     return;
 
   disabled_reason_ = new_disabled_reason;
   disabled_reason_change_callback_.Run(disabled_reason_);
 }
 
 void NTPSnippetsStatusService::GoogleSigninSucceeded(
     const std::string& account_id,
     const std::string& username,
     const std::string& password) {
-  OnStateChanged();
+  // TODO(dgn): The snippets should be refetched: https://crbug.com/650666
+  OnStateChanged(GetDisabledReasonFromDeps());
 }
 
 void NTPSnippetsStatusService::GoogleSignedOut(const std::string& account_id,
                                                const std::string& username) {
   if (!require_signin_ && disabled_reason_ == DisabledReason::NONE) {
     // Temporary enter |SIGNED_OUT| state to clear all personalised suggestions.
-    disabled_reason_change_callback_.Run(DisabledReason::SIGNED_OUT);
-    disabled_reason_change_callback_.Run(disabled_reason_);
+    OnStateChanged(DisabledReason::SIGNED_OUT);
   }
-  OnStateChanged();
+
+  // Depending on |require_signin_|, will still report as SIGNED_OUT or switch
+  // back to |DisabledReason::NONE|
+  OnStateChanged(GetDisabledReasonFromDeps());
 }
 
 DisabledReason NTPSnippetsStatusService::GetDisabledReasonFromDeps() const {
   if (!pref_service_->GetBoolean(prefs::kEnableSnippets)) {
     DVLOG(1) << "[GetNewDisabledReason] Disabled via pref";
     return DisabledReason::EXPLICITLY_DISABLED;
   }
 
   if (require_signin_ &&
       (!signin_manager_ || !signin_manager_->IsAuthenticated())) {
     DVLOG(1) << "[GetNewDisabledReason] Signed out";
     return DisabledReason::SIGNED_OUT;
   }
 
   DVLOG(1) << "[GetNewDisabledReason] Enabled";
   return DisabledReason::NONE;
 }
 
 }  // namespace ntp_snippets