Fix potential SEGV issue.

chrome/browser/ui/webui/feedback_ui.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/ui/webui/feedback_ui.h"
 
 #include <algorithm>
 #include <vector>
 
 #include "base/base64.h"
@@ skipping 44 matching lines @@
 #include "grit/locale_settings.h"
 #include "net/base/escape.h"
 #include "ui/base/resource/resource_bundle.h"
 
 #if defined(OS_CHROMEOS)
 #include "ash/shell.h"
 #include "ash/shell_delegate.h"
 #include "base/file_util.h"
 #include "base/path_service.h"
 #include "chrome/browser/chromeos/drive/drive.pb.h"
-#include "chrome/browser/chromeos/drive/drive_integration_service.h"
 #include "chrome/browser/chromeos/drive/file_system_interface.h"
 #include "chrome/browser/chromeos/drive/file_system_util.h"
 #include "chrome/browser/chromeos/login/user_manager.h"
 #include "chrome/browser/chromeos/system_logs/system_logs_fetcher_base.h"
 #include "ui/aura/root_window.h"
 #include "ui/aura/window.h"
 #endif
 
 using content::BrowserThread;
 using content::WebContents;
@@ skipping 499 matching lines @@
   ListValue screenshots_list;
   for (size_t i = 0; i < saved_screenshots->size(); ++i)
     screenshots_list.Append(new StringValue((*saved_screenshots)[i]));
   web_ui()->CallJavascriptFunction("setupSavedScreenshots", screenshots_list);
 }
 
 void FeedbackHandler::GetMostRecentScreenshotsDrive(
     const base::FilePath& filepath, std::vector<std::string>* saved_screenshots,
     size_t max_saved, base::Closure callback) {
   drive::FileSystemInterface* file_system =
-      drive::DriveIntegrationServiceFactory::GetForProfile(
-          Profile::FromWebUI(web_ui()))->file_system();
+      drive::util::GetFileSystemByProfile(Profile::FromWebUI(web_ui()));
+  if (!file_system) {
+    callback.Run();
+    return;
+  }
+
   file_system->ReadDirectoryByPath(
       drive::util::ExtractDrivePath(filepath),
       base::Bind(&ReadDirectoryCallback, max_saved, saved_screenshots,
                  callback));
 }
 #endif
 
 
 void FeedbackHandler::HandleSendReport(const ListValue* list_value) {
   if (!feedback_data_.get()) {
@@ skipping 142 matching lines @@
                     screenshot_filepaths.begin() + sort_size,
                     screenshot_filepaths.end(),
                     ScreenshotTimestampComp);
   for (size_t i = 0; i < sort_size; ++i)
     saved_screenshots->push_back(
         std::string(ScreenshotSource::kScreenshotUrlRoot) +
         std::string(ScreenshotSource::kScreenshotSaved) +
         screenshot_filepaths[i]);
 }
 #endif