Don't allow elevation for CHROME_OS.

chrome/browser/extensions/crx_installer.cc

 // Copyright (c) 2012 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/crx_installer.h"
 
 #include <map>
 #include <set>
 
 #include "base/bind.h"
@@ skipping 409 matching lines @@
   Release();  // Balanced in CheckRequirements().
   if (!requirement_errors.empty()) {
     if (error_on_unsupported_requirements_) {
       ReportFailureFromUIThread(CrxInstallerError(
           UTF8ToUTF16(JoinString(requirement_errors, ' '))));
       return;
     }
     has_requirement_errors_ = true;
   }
 
-#if defined(ENABLE_MANAGED_USERS)
+#if defined(ENABLE_MANAGED_USERS) && !defined(OS_CHROMEOS)
   // Check whether the profile is managed.
   ManagedUserService* service =
       ManagedUserServiceFactory::GetForProfile(profile_);
   if (service->ProfileIsManaged()) {
     // Extensions which should be installed by policy are installed without
     // using the ExtensionInstallPrompt. In that case, |client_| is NULL.
     if (client_ == NULL) {
       // Automatically set authorization
       OnAuthorizationResult(true);
       return;
@@ skipping 372 matching lines @@
   if (!prefs->DidExtensionEscalatePermissions(extension_->id()))
     return;
 
   if (client_) {
     AddRef();  // Balanced in InstallUIProceed() and InstallUIAbort().
     client_->ConfirmReEnable(this, extension_.get());
   }
 }
 
 }  // namespace extensions