Use DCHECKs when observing only a single notification.

chrome/browser/chromeos/login/auth/auth_prewarmer.cc

 // Copyright 2014 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 "chrome/browser/chromeos/login/auth/auth_prewarmer.h"
 
 #include <stddef.h>
 
 #include "chrome/browser/chrome_notification_types.h"
 #include "chrome/browser/chromeos/login/helper.h"
@@ skipping 59 matching lines @@
 
   NetworkHandler::Get()->network_state_handler()
       ->RemoveObserver(this, FROM_HERE);
   if (GetRequestContext())
     DoPrewarm();
 }
 
 void AuthPrewarmer::Observe(int type,
                             const content::NotificationSource& source,
                             const content::NotificationDetails& details) {
-  switch (type) {
-    case chrome::NOTIFICATION_PROFILE_URL_REQUEST_CONTEXT_GETTER_INITIALIZED:
-      registrar_.Remove(
-          this,
-          chrome::NOTIFICATION_PROFILE_URL_REQUEST_CONTEXT_GETTER_INITIALIZED,
-          content::Source<Profile>(ProfileHelper::GetSigninProfile()));
-      if (IsNetworkConnected())
-        DoPrewarm();
-      break;
-    default:
-      NOTREACHED();
-  }
+  DCHECK_EQ(chrome::NOTIFICATION_PROFILE_URL_REQUEST_CONTEXT_GETTER_INITIALIZED,
+            type);
+  registrar_.Remove(
+      this, chrome::NOTIFICATION_PROFILE_URL_REQUEST_CONTEXT_GETTER_INITIALIZED,
+      content::Source<Profile>(ProfileHelper::GetSigninProfile()));
+  if (IsNetworkConnected())
+    DoPrewarm();
 }
 
 void AuthPrewarmer::DoPrewarm() {
   const int kConnectionsNeeded = 1;
   const GURL& url = GaiaUrls::GetInstance()->service_login_url();
   content::BrowserThread::PostTask(
       content::BrowserThread::IO, FROM_HERE,
       base::Bind(&content::PreconnectUrl,
                  ProfileHelper::GetSigninProfile()->GetResourceContext(), url,
                  url, kConnectionsNeeded, true,
                  net::HttpRequestInfo::EARLY_LOAD_MOTIVATED));
   if (!completion_callback_.is_null()) {
     content::BrowserThread::PostTask(content::BrowserThread::UI, FROM_HERE,
                                      completion_callback_);
   }
 }
 
 bool AuthPrewarmer::IsNetworkConnected() const {
   NetworkStateHandler* nsh = NetworkHandler::Get()->network_state_handler();
   return (nsh->ConnectedNetworkByType(NetworkTypePattern::Default()) != NULL);
 }
 
 net::URLRequestContextGetter* AuthPrewarmer::GetRequestContext() const {
   return login::GetSigninContext();
 }
 
 }  // namespace chromeos