Change loading custom auth extension to load from --auth-ext-path value.

chrome/browser/extensions/scoped_gaia_auth_extension.cc

 // Copyright 2013 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/extensions/scoped_gaia_auth_extension.h"
 
 #include "base/command_line.h"
 #include "chrome/browser/extensions/component_loader.h"
 #include "chrome/browser/extensions/extension_service.h"
 #include "chrome/browser/extensions/extension_system.h"
@@ skipping 16 matching lines @@
   ExtensionService* extension_service = extension_system->extension_service();
   return extension_service->component_loader();
 }
 
 void LoadGaiaAuthExtension(Profile* profile) {
   extensions::ComponentLoader* component_loader = GetComponentLoader(profile);
   const CommandLine* command_line = CommandLine::ForCurrentProcess();
   if (command_line->HasSwitch(switches::kAuthExtensionPath)) {
     base::FilePath auth_extension_path =
         command_line->GetSwitchValuePath(switches::kAuthExtensionPath);
-    component_loader->Add(IDR_GAIA_TEST_AUTH_MANIFEST, auth_extension_path);
+    const std::string extension_id =
+        component_loader->AddOrReplace(auth_extension_path);
+
+    if (extension_id.empty()) {
+        LOG(ERROR) << "Failed to load custom Gaia auth extension given by the "
+            << switches::kAuthExtensionPath << " flag: "
+            << auth_extension_path.value();
+    }
     return;
   }
 
   bool force_keyboard_oobe = false;
 #if defined(OS_CHROMEOS)
   chromeos::system::StatisticsProvider* provider =
       chromeos::system::StatisticsProvider::GetInstance();
   provider->GetMachineFlag(chromeos::kOemKeyboardDrivenOobeKey,
                            &force_keyboard_oobe);
 #endif // OS_CHROMEOS
@@ skipping 14 matching lines @@
 }  // namespace
 
 ScopedGaiaAuthExtension::ScopedGaiaAuthExtension(Profile* profile)
     : profile_(profile) {
   LoadGaiaAuthExtension(profile_);
 }
 
 ScopedGaiaAuthExtension::~ScopedGaiaAuthExtension() {
   UnloadGaiaAuthExtension(profile_);
 }