Implement the new Sync Confirmation dialog on Linux and Windows.

chrome/browser/supervised_user/legacy/custodian_profile_downloader_service.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/supervised_user/legacy/custodian_profile_downloader_service.h"
 
 #include "base/prefs/pref_service.h"
 #include "chrome/browser/profiles/profile.h"
 #include "chrome/browser/signin/signin_manager_factory.h"
 #include "chrome/common/pref_names.h"
@@ skipping 32 matching lines @@
   // failing somehow than that the new one won't succeed.
   in_progress_profile_email_ = current_email;
   profile_downloader_.reset(new ProfileDownloader(this));
   profile_downloader_->Start();
 }
 
 bool CustodianProfileDownloaderService::NeedsProfilePicture() const {
   return false;
 }
 
-int CustodianProfileDownloaderService::GetDesiredImageSideLength() const {
+unsigned int CustodianProfileDownloaderService::GetDesiredImageSideLength()
+    const {
   return 0;
 }
 
 std::string CustodianProfileDownloaderService::GetCachedPictureURL() const {
   return std::string();
 }
 
 Profile* CustodianProfileDownloaderService::GetBrowserProfile() {
   DCHECK(custodian_profile_);
   return custodian_profile_;
@@ skipping 10 matching lines @@
   last_downloaded_profile_email_ = in_progress_profile_email_;
 }
 
 void CustodianProfileDownloaderService::OnProfileDownloadFailure(
     ProfileDownloader* downloader,
     ProfileDownloaderDelegate::FailureReason reason) {
   // Ignore failures; proceed without the custodian's name.
   download_callback_.Reset();
   profile_downloader_.reset();
 }