Move chrome.fileSystem implementation to //extensions

chrome/browser/extensions/api/file_system/chrome_file_system_delegate.cc

-// Copyright (c) 2012 The Chromium Authors. All rights reserved.
+// Copyright 2017 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/api/file_system/file_system_api.h"
+#include "chrome/browser/extensions/api/file_system/chrome_file_system_delegate.h"
 
-#include <stddef.h>
-
-#include <memory>
-#include <set>
 #include <utility>
 #include <vector>
 
 #include "apps/saved_files_service.h"
 #include "base/bind.h"
 #include "base/callback.h"
 #include "base/files/file_path.h"
-#include "base/files/file_util.h"
-#include "base/macros.h"
+#include "base/logging.h"
 #include "base/memory/ptr_util.h"
 #include "base/path_service.h"
-#include "base/stl_util.h"
-#include "base/strings/string_util.h"
-#include "base/strings/stringprintf.h"
-#include "base/strings/sys_string_conversions.h"
-#include "base/strings/utf_string_conversions.h"
-#include "base/task_scheduler/post_task.h"
-#include "base/value_conversions.h"
-#include "base/values.h"
-#include "build/build_config.h"
+#include "base/strings/string16.h"
 #include "chrome/browser/extensions/api/file_system/file_entry_picker.h"
-#include "chrome/browser/platform_util.h"
+#include "chrome/browser/extensions/chrome_extension_function_details.h"
 #include "chrome/browser/profiles/profile.h"
 #include "chrome/browser/ui/apps/directory_access_confirmation_dialog.h"
-#include "chrome/browser/ui/chrome_select_file_policy.h"
 #include "chrome/common/chrome_paths.h"
-#include "chrome/common/extensions/api/file_system.h"
 #include "chrome/grit/generated_resources.h"
-#include "content/public/browser/browser_thread.h"
+#include "content/public/browser/browser_context.h"
 #include "content/public/browser/child_process_security_policy.h"
 #include "content/public/browser/render_frame_host.h"
 #include "content/public/browser/render_process_host.h"
 #include "content/public/browser/storage_partition.h"
 #include "content/public/browser/web_contents.h"
 #include "extensions/browser/api/file_handlers/app_file_handler_util.h"
-#include "extensions/browser/api/file_system/saved_file_entry.h"
+#include "extensions/browser/api/file_system/saved_files_service_interface.h"
 #include "extensions/browser/app_window/app_window.h"
 #include "extensions/browser/app_window/app_window_registry.h"
+#include "extensions/browser/extension_function.h"
 #include "extensions/browser/extension_prefs.h"
 #include "extensions/browser/extension_system.h"
 #include "extensions/browser/extension_util.h"
-#include "extensions/browser/granted_file_entry.h"
-#include "extensions/browser/path_util.h"
-#include "extensions/common/permissions/api_permission.h"
-#include "extensions/common/permissions/permissions_data.h"
-#include "net/base/mime_util.h"
+#include "extensions/common/api/file_system.h"
+#include "extensions/common/extension.h"
 #include "storage/browser/fileapi/external_mount_points.h"
-#include "storage/browser/fileapi/file_system_operation_runner.h"
 #include "storage/browser/fileapi/isolated_context.h"
 #include "storage/common/fileapi/file_system_types.h"
 #include "storage/common/fileapi/file_system_util.h"
-#include "ui/base/l10n/l10n_util.h"
-#include "ui/base/ui_base_types.h"
 #include "ui/shell_dialogs/select_file_dialog.h"
-#include "ui/shell_dialogs/select_file_policy.h"
 
 #if defined(OS_MACOSX)
 #include <CoreFoundation/CoreFoundation.h>
 #include "base/mac/foundation_util.h"
 #endif
 
 #if defined(OS_CHROMEOS)
-#include "base/strings/string16.h"
-#include "chrome/browser/chromeos/file_manager/filesystem_api_util.h"
 #include "chrome/browser/chromeos/file_manager/volume_manager.h"
+#include "chrome/browser/extensions/api/file_system/consent_provider.h"
 #include "extensions/browser/event_router.h"
 #include "extensions/browser/extension_registry.h"
 #include "extensions/common/constants.h"
 #include "url/url_constants.h"
 #endif
 
-using apps::SavedFilesService;
-using storage::IsolatedContext;
-
-const char kInvalidCallingPage[] =
-    "Invalid calling page. "
-    "This function can't be called from a background page.";
-const char kUserCancelled[] = "User cancelled";
-const char kWritableFileErrorFormat[] = "Error opening %s";
+namespace extensions {
+
+namespace file_system = api::file_system;
+
+#if defined(OS_CHROMEOS)
+using file_system_api::ConsentProvider;
+using file_system_api::ConsentProviderDelegate;
+
+namespace {
+
+const char kConsentImpossible[] =
+    "Impossible to ask for user consent as there is no app window visible.";
+const char kNotSupportedOnNonKioskSessionError[] =
+    "Operation only supported for kiosk apps running in a kiosk session.";
 const char kRequiresFileSystemWriteError[] =
     "Operation requires fileSystem.write permission";
-const char kRequiresFileSystemDirectoryError[] =
-    "Operation requires fileSystem.directory permission";
-const char kMultipleUnsupportedError[] =
-    "acceptsMultiple: true is only supported for 'openFile'";
-const char kUnknownIdError[] = "Unknown id";
-
-#if !defined(OS_CHROMEOS)
-const char kNotSupportedOnCurrentPlatformError[] =
-    "Operation not supported on the current platform.";
-#else
-const char kNotSupportedOnNonKioskSessionError[] =
-    "Operation only supported for kiosk apps running in a kiosk session.";
+const char kSecurityError[] = "Security error.";
 const char kVolumeNotFoundError[] = "Volume not found.";
-const char kSecurityError[] = "Security error.";
-const char kConsentImpossible[] =
-    "Impossible to ask for user consent as there is no app window visible.";
-#endif
-
-namespace extensions {
-
-namespace file_system = api::file_system;
-namespace ChooseEntry = file_system::ChooseEntry;
-
-namespace {
-
-bool g_skip_picker_for_test = false;
-bool g_use_suggested_path_for_test = false;
-base::FilePath* g_path_to_be_picked_for_test;
-std::vector<base::FilePath>* g_paths_to_be_picked_for_test;
-bool g_skip_directory_confirmation_for_test = false;
-bool g_allow_directory_access_for_test = false;
-
-// Expand the mime-types and extensions provided in an AcceptOption, returning
-// them within the passed extension vector. Returns false if no valid types
-// were found.
-bool GetFileTypesFromAcceptOption(
-    const file_system::AcceptOption& accept_option,
-    std::vector<base::FilePath::StringType>* extensions,
-    base::string16* description) {
-  std::set<base::FilePath::StringType> extension_set;
-  int description_id = 0;
-
-  if (accept_option.mime_types.get()) {
-    std::vector<std::string>* list = accept_option.mime_types.get();
-    bool valid_type = false;
-    for (std::vector<std::string>::const_iterator iter = list->begin();
-         iter != list->end(); ++iter) {
-      std::vector<base::FilePath::StringType> inner;
-      std::string accept_type = base::ToLowerASCII(*iter);
-      net::GetExtensionsForMimeType(accept_type, &inner);
-      if (inner.empty())
-        continue;
-
-      if (valid_type)
-        description_id = 0;  // We already have an accept type with label; if
-                             // we find another, give up and use the default.
-      else if (accept_type == "image/*")
-        description_id = IDS_IMAGE_FILES;
-      else if (accept_type == "audio/*")
-        description_id = IDS_AUDIO_FILES;
-      else if (accept_type == "video/*")
-        description_id = IDS_VIDEO_FILES;
-
-      extension_set.insert(inner.begin(), inner.end());
-      valid_type = true;
-    }
-  }
-
-  if (accept_option.extensions.get()) {
-    std::vector<std::string>* list = accept_option.extensions.get();
-    for (std::vector<std::string>::const_iterator iter = list->begin();
-         iter != list->end(); ++iter) {
-      std::string extension = base::ToLowerASCII(*iter);
-#if defined(OS_WIN)
-      extension_set.insert(base::UTF8ToWide(*iter));
-#else
-      extension_set.insert(*iter);
-#endif
-    }
-  }
-
-  extensions->assign(extension_set.begin(), extension_set.end());
-  if (extensions->empty())
-    return false;
-
-  if (accept_option.description.get())
-    *description = base::UTF8ToUTF16(*accept_option.description);
-  else if (description_id)
-    *description = l10n_util::GetStringUTF16(description_id);
-
-  return true;
-}
-
-// Key for the path of the directory of the file last chosen by the user in
-// response to a chrome.fileSystem.chooseEntry() call.
-const char kLastChooseEntryDirectory[] = "last_choose_file_directory";
-
-const int kGraylistedPaths[] = {
-    base::DIR_HOME,
-#if defined(OS_WIN)
-    base::DIR_PROGRAM_FILES, base::DIR_PROGRAM_FILESX86, base::DIR_WINDOWS,
-#endif
-};
-
-typedef base::Callback<void(std::unique_ptr<base::File::Info>)>
-    FileInfoOptCallback;
-
-// Passes optional file info to the UI thread depending on |result| and |info|.
-void PassFileInfoToUIThread(const FileInfoOptCallback& callback,
-                            base::File::Error result,
-                            const base::File::Info& info) {
-  DCHECK_CURRENTLY_ON(content::BrowserThread::IO);
-  std::unique_ptr<base::File::Info> file_info(
-      result == base::File::FILE_OK ? new base::File::Info(info) : NULL);
-  content::BrowserThread::PostTask(
-      content::BrowserThread::UI, FROM_HERE,
-      base::BindOnce(callback, base::Passed(&file_info)));
-}
-
-// Gets a WebContents instance handle for a platform app hosted in
-// |render_frame_host|. If not found, then returns NULL.
-content::WebContents* GetWebContentsForRenderFrameHost(
-    content::BrowserContext* browser_context,
-    content::RenderFrameHost* render_frame_host) {
-  content::WebContents* web_contents =
-      content::WebContents::FromRenderFrameHost(render_frame_host);
-  // Check if there is an app window associated with the web contents; if not,
-  // return null.
-  return AppWindowRegistry::Get(browser_context)
-                 ->GetAppWindowForWebContents(web_contents)
-             ? web_contents
-             : nullptr;
-}
-
-#if defined(OS_CHROMEOS)
+
 // Fills a list of volumes mounted in the system.
-void FillVolumeList(Profile* profile,
-                    std::vector<api::file_system::Volume>* result) {
+void FillVolumeList(content::BrowserContext* browser_context,
+                    std::vector<file_system::Volume>* result) {
   file_manager::VolumeManager* const volume_manager =
-      file_manager::VolumeManager::Get(profile);
+      file_manager::VolumeManager::Get(browser_context);
   DCHECK(volume_manager);
 
   const auto& volume_list = volume_manager->GetVolumeList();
   // Convert volume_list to result_volume_list.
   for (const auto& volume : volume_list) {
-    api::file_system::Volume result_volume;
+    file_system::Volume result_volume;
     result_volume.volume_id = volume->volume_id();
     result_volume.writable = !volume->is_read_only();
     result->push_back(std::move(result_volume));
   }
 }
-#endif
-
-// Creates and shows a SelectFileDialog, or returns false if the dialog could
-// not be created.
-bool ShowSelectFileDialog(
+
+// Callback called when consent is granted or denied.
+void OnConsentReceived(
+    content::BrowserContext* browser_context,
+    scoped_refptr<UIThreadExtensionFunction> requester,
+    const FileSystemDelegate::FileSystemCallback& success_callback,
+    const FileSystemDelegate::ErrorCallback& error_callback,
+    const std::string& extension_id,
+    const base::WeakPtr<file_manager::Volume>& volume,
+    bool writable,
+    ConsentProvider::Consent result) {
+  using file_manager::VolumeManager;
+  using file_manager::Volume;
+
+  // Render frame host can be gone before this callback method is executed.
+  if (!requester->render_frame_host()) {
+    error_callback.Run(std::string());
+    return;
+  }
+
+  switch (result) {
+    case ConsentProvider::CONSENT_REJECTED:
+      error_callback.Run(kSecurityError);
+      return;
+
+    case ConsentProvider::CONSENT_IMPOSSIBLE:
+      error_callback.Run(kConsentImpossible);
+      return;
+
+    case ConsentProvider::CONSENT_GRANTED:
+      break;
+  }
+
+  if (!volume.get()) {
+    error_callback.Run(kVolumeNotFoundError);
+    return;
+  }
+
+  const GURL site = util::GetSiteForExtensionId(extension_id, browser_context);
+  scoped_refptr<storage::FileSystemContext> file_system_context =
+      content::BrowserContext::GetStoragePartitionForSite(browser_context, site)
+          ->GetFileSystemContext();
+  storage::ExternalFileSystemBackend* const backend =
+      file_system_context->external_backend();
+  DCHECK(backend);
+
+  base::FilePath virtual_path;
+  if (!backend->GetVirtualPath(volume->mount_path(), &virtual_path)) {
+    error_callback.Run(kSecurityError);
+    return;
+  }
+
+  storage::IsolatedContext* const isolated_context =
+      storage::IsolatedContext::GetInstance();
+  DCHECK(isolated_context);
+
+  const storage::FileSystemURL original_url =
+      file_system_context->CreateCrackedFileSystemURL(
+          GURL(std::string(kExtensionScheme) + url::kStandardSchemeSeparator +
+               extension_id),
+          storage::kFileSystemTypeExternal, virtual_path);
+
+  // Set a fixed register name, as the automatic one would leak the mount point
+  // directory.
+  std::string register_name = "fs";
+  const std::string file_system_id =
+      isolated_context->RegisterFileSystemForPath(
+          storage::kFileSystemTypeNativeForPlatformApp,
+          std::string() /* file_system_id */, original_url.path(),
+          &register_name);
+  if (file_system_id.empty()) {
+    error_callback.Run(kSecurityError);
+    return;
+  }
+
+  backend->GrantFileAccessToExtension(extension_id, virtual_path);
+
+  // Grant file permissions to the renderer hosting component.
+  content::ChildProcessSecurityPolicy* policy =
+      content::ChildProcessSecurityPolicy::GetInstance();
+  DCHECK(policy);
+
+  const auto process_id = requester->render_frame_host()->GetProcess()->GetID();
+  // Read-only permisisons.
+  policy->GrantReadFile(process_id, volume->mount_path());
+  policy->GrantReadFileSystem(process_id, file_system_id);
+
+  // Additional write permissions.
+  if (writable) {
+    policy->GrantCreateReadWriteFile(process_id, volume->mount_path());
+    policy->GrantCopyInto(process_id, volume->mount_path());
+    policy->GrantWriteFileSystem(process_id, file_system_id);
+    policy->GrantDeleteFromFileSystem(process_id, file_system_id);
+    policy->GrantCreateFileForFileSystem(process_id, file_system_id);
+  }
+
+  success_callback.Run(file_system_id, register_name);
+}
+
+}  // namespace
+
+namespace file_system_api {
+
+void DispatchVolumeListChangeEvent(content::BrowserContext* browser_context) {
+  DCHECK(browser_context);
+  EventRouter* const event_router = EventRouter::Get(browser_context);
+  if (!event_router)  // Possible on shutdown.
+    return;
+
+  ExtensionRegistry* const registry = ExtensionRegistry::Get(browser_context);
+  if (!registry)  // Possible on shutdown.
+    return;
+
+  ConsentProviderDelegate consent_provider_delegate(
+      Profile::FromBrowserContext(browser_context));
+  ConsentProvider consent_provider(&consent_provider_delegate);
+  file_system::VolumeListChangedEvent event_args;
+  FillVolumeList(browser_context, &event_args.volumes);
+  for (const auto& extension : registry->enabled_extensions()) {
+    if (!consent_provider.IsGrantable(*extension.get()))
+      continue;
+    event_router->DispatchEventToExtension(
+        extension->id(),
+        base::MakeUnique<Event>(
+            events::FILE_SYSTEM_ON_VOLUME_LIST_CHANGED,
+            file_system::OnVolumeListChanged::kEventName,
+            file_system::OnVolumeListChanged::Create(event_args)));
+  }
+}
+
+}  // namespace file_system_api
+#endif  // defined(OS_CHROMEOS)
+
+ChromeFileSystemDelegate::ChromeFileSystemDelegate() {}
+
+ChromeFileSystemDelegate::~ChromeFileSystemDelegate() {}
+
+base::FilePath ChromeFileSystemDelegate::GetDefaultDirectory() {
+  base::FilePath documents_dir;
+  PathService::Get(chrome::DIR_USER_DOCUMENTS, &documents_dir);
+  return documents_dir;
+}
+
+bool ChromeFileSystemDelegate::ShowSelectFileDialog(
     scoped_refptr<UIThreadExtensionFunction> extension_function,
     ui::SelectFileDialog::Type type,
     const base::FilePath& default_path,
     const ui::SelectFileDialog::FileTypeInfo* file_types,
-    FileEntryPicker::FilesSelectedCallback files_selected_callback,
+    FileSystemDelegate::FilesSelectedCallback files_selected_callback,
     base::OnceClosure file_selection_canceled_callback) {
+  const Extension* extension = extension_function->extension();
+  content::WebContents* web_contents = nullptr;
+
   // TODO(asargent/benwells) - As a short term remediation for
   // crbug.com/179010 we're adding the ability for a whitelisted extension to
   // use this API since chrome.fileBrowserHandler.selectFile is ChromeOS-only.
   // Eventually we'd like a better solution and likely this code will go back
   // to being platform-app only.
-  content::WebContents* const web_contents =
-      extension_function->extension()->is_platform_app()
-          ? GetWebContentsForRenderFrameHost(
-                extension_function->browser_context(),
-                extension_function->render_frame_host())
-          : extension_function->GetAssociatedWebContents();
+  if (extension->is_platform_app()) {
+    content::WebContents* candidate = content::WebContents::FromRenderFrameHost(
+        extension_function->render_frame_host());
+    // Make sure there is an app window associated with the web contents.
+    if (AppWindowRegistry::Get(extension_function->browser_context())
+            ->GetAppWindowForWebContents(candidate)) {
+      web_contents = candidate;
+    }
+  } else {
+    // TODO(michaelpg): As a workaround for crbug.com/736930, allow this to work
+    // from a background page by using the the extended GetAssociatedWebContents
+    // function provided by ChromeExtensionFunctionDetails. This is safe because
+    // only whitelisted extensions can access the chrome.fileSystem API;
+    // platform apps cannot open the file picker from a background page.
+    web_contents = ChromeExtensionFunctionDetails(extension_function.get())
+                       .GetAssociatedWebContents();
+  }
+
   if (!web_contents)
     return false;
 
   // The file picker will hold a reference to the UIThreadExtensionFunction
   // instance, preventing its destruction (and subsequent sending of the
   // function response) until the user has selected a file or cancelled the
   // picker. At that point, the picker will delete itself, which will also free
   // the function instance.
   new FileEntryPicker(web_contents, default_path, *file_types, type,
                       std::move(files_selected_callback),
                       std::move(file_selection_canceled_callback));
   return true;
 }
 
-}  // namespace
-
-namespace file_system_api {
-
-base::FilePath GetLastChooseEntryDirectory(const ExtensionPrefs* prefs,
-                                           const std::string& extension_id) {
-  base::FilePath path;
-  std::string string_path;
-  if (prefs->ReadPrefAsString(extension_id, kLastChooseEntryDirectory,
-                              &string_path)) {
-    path = base::FilePath::FromUTF8Unsafe(string_path);
-  }
-  return path;
-}
-
-void SetLastChooseEntryDirectory(ExtensionPrefs* prefs,
-                                 const std::string& extension_id,
-                                 const base::FilePath& path) {
-  prefs->UpdateExtensionPref(extension_id, kLastChooseEntryDirectory,
-                             base::CreateFilePathValue(path));
+void ChromeFileSystemDelegate::ConfirmSensitiveDirectoryAccess(
+    bool has_write_permission,
+    const base::string16& app_name,
+    content::WebContents* web_contents,
+    const base::Closure& on_accept,
+    const base::Closure& on_cancel) {
+  CreateDirectoryAccessConfirmationDialog(has_write_permission, app_name,
+                                          web_contents, on_accept, on_cancel);
+}
+
+int ChromeFileSystemDelegate::GetDescriptionIdForAcceptType(
+    const std::string& accept_type) {
+  if (accept_type == "image/*")
+    return IDS_IMAGE_FILES;
+  if (accept_type == "audio/*")
+    return IDS_AUDIO_FILES;
+  if (accept_type == "video/*")
+    return IDS_VIDEO_FILES;
+  return 0;
 }
 
 #if defined(OS_CHROMEOS)
-void DispatchVolumeListChangeEvent(Profile* profile) {
-  DCHECK(profile);
-  EventRouter* const event_router = EventRouter::Get(profile);
-  if (!event_router)  // Possible on shutdown.
-    return;
-
-  ExtensionRegistry* const registry = ExtensionRegistry::Get(profile);
-  if (!registry)  // Possible on shutdown.
-    return;
-
-  ConsentProviderDelegate consent_provider_delegate(profile, nullptr);
-  ConsentProvider consent_provider(&consent_provider_delegate);
-  api::file_system::VolumeListChangedEvent event_args;
-  FillVolumeList(profile, &event_args.volumes);
-  for (const auto& extension : registry->enabled_extensions()) {
-    if (!consent_provider.IsGrantable(*extension.get()))
-      continue;
-    event_router->DispatchEventToExtension(
-        extension->id(),
-        base::MakeUnique<Event>(
-            events::FILE_SYSTEM_ON_VOLUME_LIST_CHANGED,
-            api::file_system::OnVolumeListChanged::kEventName,
-            api::file_system::OnVolumeListChanged::Create(event_args)));
-  }
-}
-#endif
-
-}  // namespace file_system_api
-
-#if defined(OS_CHROMEOS)
-using file_system_api::ConsentProvider;
-#endif
-
-ExtensionFunction::ResponseAction FileSystemGetDisplayPathFunction::Run() {
-  std::string filesystem_name;
-  std::string filesystem_path;
-  EXTENSION_FUNCTION_VALIDATE(args_->GetString(0, &filesystem_name));
-  EXTENSION_FUNCTION_VALIDATE(args_->GetString(1, &filesystem_path));
-
-  base::FilePath file_path;
-  std::string error;
-  if (!app_file_handler_util::ValidateFileEntryAndGetPath(
-          filesystem_name, filesystem_path,
-          render_frame_host()->GetProcess()->GetID(), &file_path, &error)) {
-    return RespondNow(Error(error));
-  }
-
-  file_path = path_util::PrettifyPath(file_path);
-  return RespondNow(
-      OneArgument(base::MakeUnique<base::Value>(file_path.value())));
-}
-
-FileSystemEntryFunction::FileSystemEntryFunction()
-    : multiple_(false), is_directory_(false) {}
-
-void FileSystemEntryFunction::PrepareFilesForWritableApp(
-    const std::vector<base::FilePath>& paths) {
-  DCHECK_CURRENTLY_ON(content::BrowserThread::UI);
-  // TODO(cmihail): Path directory set should be initialized only with the
-  // paths that are actually directories, but for now we will consider
-  // all paths directories in case is_directory_ is true, otherwise
-  // all paths files, as this was the previous logic.
-  std::set<base::FilePath> path_directory_set_ =
-      is_directory_ ? std::set<base::FilePath>(paths.begin(), paths.end())
-                    : std::set<base::FilePath>{};
-  app_file_handler_util::PrepareFilesForWritableApp(
-      paths, GetProfile(), path_directory_set_,
-      base::Bind(&FileSystemEntryFunction::RegisterFileSystemsAndSendResponse,
-                 this, paths),
-      base::Bind(&FileSystemEntryFunction::HandleWritableFileError, this));
-}
-
-void FileSystemEntryFunction::RegisterFileSystemsAndSendResponse(
-    const std::vector<base::FilePath>& paths) {
-  DCHECK_CURRENTLY_ON(content::BrowserThread::UI);
-  if (!render_frame_host())
-    return;
-
-  std::unique_ptr<base::DictionaryValue> result = CreateResult();
-  for (const auto& path : paths)
-    AddEntryToResult(path, std::string(), result.get());
-  SetResult(std::move(result));
-  SendResponse(true);
-}
-
-std::unique_ptr<base::DictionaryValue> FileSystemEntryFunction::CreateResult() {
-  std::unique_ptr<base::DictionaryValue> result(new base::DictionaryValue());
-  result->Set("entries", base::MakeUnique<base::ListValue>());
-  result->SetBoolean("multiple", multiple_);
-  return result;
-}
-
-void FileSystemEntryFunction::AddEntryToResult(const base::FilePath& path,
-                                               const std::string& id_override,
-                                               base::DictionaryValue* result) {
-  GrantedFileEntry file_entry = app_file_handler_util::CreateFileEntry(
-      GetProfile(), extension(), render_frame_host()->GetProcess()->GetID(),
-      path, is_directory_);
-  base::ListValue* entries;
-  bool success = result->GetList("entries", &entries);
-  DCHECK(success);
-
-  std::unique_ptr<base::DictionaryValue> entry(new base::DictionaryValue());
-  entry->SetString("fileSystemId", file_entry.filesystem_id);
-  entry->SetString("baseName", file_entry.registered_name);
-  if (id_override.empty())
-    entry->SetString("id", file_entry.id);
-  else
-    entry->SetString("id", id_override);
-  entry->SetBoolean("isDirectory", is_directory_);
-  entries->Append(std::move(entry));
-}
-
-void FileSystemEntryFunction::HandleWritableFileError(
-    const base::FilePath& error_path) {
-  DCHECK_CURRENTLY_ON(content::BrowserThread::UI);
-  error_ = base::StringPrintf(kWritableFileErrorFormat,
-                              error_path.BaseName().AsUTF8Unsafe().c_str());
-  SendResponse(false);
-}
-
-bool FileSystemGetWritableEntryFunction::RunAsync() {
-  std::string filesystem_name;
-  std::string filesystem_path;
-  EXTENSION_FUNCTION_VALIDATE(args_->GetString(0, &filesystem_name));
-  EXTENSION_FUNCTION_VALIDATE(args_->GetString(1, &filesystem_path));
-
-  if (!app_file_handler_util::HasFileSystemWritePermission(extension_.get())) {
-    error_ = kRequiresFileSystemWriteError;
-    return false;
-  }
-
-  if (!app_file_handler_util::ValidateFileEntryAndGetPath(
-          filesystem_name, filesystem_path,
-          render_frame_host()->GetProcess()->GetID(), &path_, &error_))
-    return false;
-
-  base::PostTaskWithTraitsAndReply(
-      FROM_HERE, {base::MayBlock(), base::TaskPriority::BACKGROUND},
-      base::BindOnce(&FileSystemGetWritableEntryFunction::SetIsDirectoryAsync,
-                     this),
-      base::BindOnce(
-          &FileSystemGetWritableEntryFunction::CheckPermissionAndSendResponse,
-          this));
-  return true;
-}
-
-void FileSystemGetWritableEntryFunction::CheckPermissionAndSendResponse() {
-  DCHECK_CURRENTLY_ON(content::BrowserThread::UI);
-  if (is_directory_ && !extension_->permissions_data()->HasAPIPermission(
-                           APIPermission::kFileSystemDirectory)) {
-    error_ = kRequiresFileSystemDirectoryError;
-    SendResponse(false);
-  }
-  std::vector<base::FilePath> paths;
-  paths.push_back(path_);
-  PrepareFilesForWritableApp(paths);
-}
-
-void FileSystemGetWritableEntryFunction::SetIsDirectoryAsync() {
-  if (base::DirectoryExists(path_)) {
-    is_directory_ = true;
-  }
-}
-
-ExtensionFunction::ResponseAction FileSystemIsWritableEntryFunction::Run() {
-  std::string filesystem_name;
-  std::string filesystem_path;
-  EXTENSION_FUNCTION_VALIDATE(args_->GetString(0, &filesystem_name));
-  EXTENSION_FUNCTION_VALIDATE(args_->GetString(1, &filesystem_path));
-
-  std::string filesystem_id;
-  if (!storage::CrackIsolatedFileSystemName(filesystem_name, &filesystem_id))
-    return RespondNow(Error(app_file_handler_util::kInvalidParameters));
-
-  content::ChildProcessSecurityPolicy* policy =
-      content::ChildProcessSecurityPolicy::GetInstance();
-  int renderer_id = render_frame_host()->GetProcess()->GetID();
-  bool is_writable = policy->CanReadWriteFileSystem(renderer_id, filesystem_id);
-
-  return RespondNow(OneArgument(base::MakeUnique<base::Value>(is_writable)));
-}
-
-void FileSystemChooseEntryFunction::ShowPicker(
-    const ui::SelectFileDialog::FileTypeInfo& file_type_info,
-    ui::SelectFileDialog::Type picker_type) {
-  if (g_skip_picker_for_test) {
-    std::vector<base::FilePath> test_paths;
-    if (g_use_suggested_path_for_test)
-      test_paths.push_back(initial_path_);
-    else if (g_path_to_be_picked_for_test)
-      test_paths.push_back(*g_path_to_be_picked_for_test);
-    else if (g_paths_to_be_picked_for_test)
-      test_paths = *g_paths_to_be_picked_for_test;
-
-    content::BrowserThread::PostTask(
-        content::BrowserThread::UI, FROM_HERE,
-        test_paths.size() > 0
-            ? base::BindOnce(&FileSystemChooseEntryFunction::FilesSelected,
-                             this, test_paths)
-            : base::BindOnce(
-                  &FileSystemChooseEntryFunction::FileSelectionCanceled, this));
-    return;
-  }
-
-  // The callbacks passed to the dialog will retain references to this
-  // UIThreadExtenisonFunction, preventing its destruction (and subsequent
-  // sending of the function response) until the user has selected a file or
-  // cancelled the picker.
-  if (!ShowSelectFileDialog(
-          this, picker_type, initial_path_, &file_type_info,
-          base::BindOnce(&FileSystemChooseEntryFunction::FilesSelected, this),
-          base::BindOnce(&FileSystemChooseEntryFunction::FileSelectionCanceled,
-                         this))) {
-    error_ = kInvalidCallingPage;
-    SendResponse(false);
-  }
-}
-
-// static
-void FileSystemChooseEntryFunction::SkipPickerAndAlwaysSelectPathForTest(
-    base::FilePath* path) {
-  g_skip_picker_for_test = true;
-  g_use_suggested_path_for_test = false;
-  g_path_to_be_picked_for_test = path;
-  g_paths_to_be_picked_for_test = NULL;
-}
-
-void FileSystemChooseEntryFunction::SkipPickerAndAlwaysSelectPathsForTest(
-    std::vector<base::FilePath>* paths) {
-  g_skip_picker_for_test = true;
-  g_use_suggested_path_for_test = false;
-  g_paths_to_be_picked_for_test = paths;
-}
-
-// static
-void FileSystemChooseEntryFunction::SkipPickerAndSelectSuggestedPathForTest() {
-  g_skip_picker_for_test = true;
-  g_use_suggested_path_for_test = true;
-  g_path_to_be_picked_for_test = NULL;
-  g_paths_to_be_picked_for_test = NULL;
-}
-
-// static
-void FileSystemChooseEntryFunction::SkipPickerAndAlwaysCancelForTest() {
-  g_skip_picker_for_test = true;
-  g_use_suggested_path_for_test = false;
-  g_path_to_be_picked_for_test = NULL;
-  g_paths_to_be_picked_for_test = NULL;
-}
-
-// static
-void FileSystemChooseEntryFunction::StopSkippingPickerForTest() {
-  g_skip_picker_for_test = false;
-}
-
-// static
-void FileSystemChooseEntryFunction::SkipDirectoryConfirmationForTest() {
-  g_skip_directory_confirmation_for_test = true;
-  g_allow_directory_access_for_test = true;
-}
-
-// static
-void FileSystemChooseEntryFunction::AutoCancelDirectoryConfirmationForTest() {
-  g_skip_directory_confirmation_for_test = true;
-  g_allow_directory_access_for_test = false;
-}
-
-// static
-void FileSystemChooseEntryFunction::StopSkippingDirectoryConfirmationForTest() {
-  g_skip_directory_confirmation_for_test = false;
-}
-
-// static
-void FileSystemChooseEntryFunction::RegisterTempExternalFileSystemForTest(
-    const std::string& name,
-    const base::FilePath& path) {
-  // For testing on Chrome OS, where to deal with remote and local paths
-  // smoothly, all accessed paths need to be registered in the list of
-  // external mount points.
-  storage::ExternalMountPoints::GetSystemInstance()->RegisterFileSystem(
-      name, storage::kFileSystemTypeNativeLocal,
-      storage::FileSystemMountOption(), path);
-}
-
-void FileSystemChooseEntryFunction::FilesSelected(
-    const std::vector<base::FilePath>& paths) {
-  DCHECK(!paths.empty());
-  base::FilePath last_choose_directory;
-  if (is_directory_) {
-    last_choose_directory = paths[0];
-  } else {
-    last_choose_directory = paths[0].DirName();
-  }
-  file_system_api::SetLastChooseEntryDirectory(
-      ExtensionPrefs::Get(GetProfile()), extension()->id(),
-      last_choose_directory);
-  if (is_directory_) {
-    // Get the WebContents for the app window to be the parent window of the
-    // confirmation dialog if necessary.
-    content::WebContents* const web_contents =
-        GetWebContentsForRenderFrameHost(GetProfile(), render_frame_host());
-    if (!web_contents) {
-      error_ = kInvalidCallingPage;
-      SendResponse(false);
-      return;
-    }
-
-    DCHECK_EQ(paths.size(), 1u);
-    bool non_native_path = false;
-#if defined(OS_CHROMEOS)
-    non_native_path =
-        file_manager::util::IsUnderNonNativeLocalPath(GetProfile(), paths[0]);
-#endif
-
-    base::PostTaskWithTraits(
-        FROM_HERE, {base::MayBlock(), base::TaskPriority::BACKGROUND},
-        base::BindOnce(
-            &FileSystemChooseEntryFunction::ConfirmDirectoryAccessAsync, this,
-            non_native_path, paths, web_contents));
-    return;
-  }
-
-  OnDirectoryAccessConfirmed(paths);
-}
-
-void FileSystemChooseEntryFunction::FileSelectionCanceled() {
-  error_ = kUserCancelled;
-  SendResponse(false);
-}
-
-void FileSystemChooseEntryFunction::ConfirmDirectoryAccessAsync(
-    bool non_native_path,
-    const std::vector<base::FilePath>& paths,
-    content::WebContents* web_contents) {
-  const base::FilePath check_path =
-      non_native_path ? paths[0] : base::MakeAbsoluteFilePath(paths[0]);
-  if (check_path.empty()) {
-    content::BrowserThread::PostTask(
-        content::BrowserThread::UI, FROM_HERE,
-        base::BindOnce(&FileSystemChooseEntryFunction::FileSelectionCanceled,
-                       this));
-    return;
-  }
-
-  for (size_t i = 0; i < arraysize(kGraylistedPaths); i++) {
-    base::FilePath graylisted_path;
-    if (PathService::Get(kGraylistedPaths[i], &graylisted_path) &&
-        (check_path == graylisted_path ||
-         check_path.IsParent(graylisted_path))) {
-      if (g_skip_directory_confirmation_for_test) {
-        if (g_allow_directory_access_for_test) {
-          break;
-        } else {
-          content::BrowserThread::PostTask(
-              content::BrowserThread::UI, FROM_HERE,
-              base::BindOnce(
-                  &FileSystemChooseEntryFunction::FileSelectionCanceled, this));
-        }
-        return;
-      }
-
-      content::BrowserThread::PostTask(
-          content::BrowserThread::UI, FROM_HERE,
-          base::BindOnce(
-              CreateDirectoryAccessConfirmationDialog,
-              app_file_handler_util::HasFileSystemWritePermission(
-                  extension_.get()),
-              base::UTF8ToUTF16(extension_->name()), web_contents,
-              base::Bind(
-                  &FileSystemChooseEntryFunction::OnDirectoryAccessConfirmed,
-                  this, paths),
-              base::Bind(&FileSystemChooseEntryFunction::FileSelectionCanceled,
-                         this)));
-      return;
-    }
-  }
-
-  content::BrowserThread::PostTask(
-      content::BrowserThread::UI, FROM_HERE,
-      base::BindOnce(&FileSystemChooseEntryFunction::OnDirectoryAccessConfirmed,
-                     this, paths));
-}
-
-void FileSystemChooseEntryFunction::OnDirectoryAccessConfirmed(
-    const std::vector<base::FilePath>& paths) {
-  if (app_file_handler_util::HasFileSystemWritePermission(extension_.get())) {
-    PrepareFilesForWritableApp(paths);
-    return;
-  }
-
-  // Don't need to check the file, it's for reading.
-  RegisterFileSystemsAndSendResponse(paths);
-}
-
-void FileSystemChooseEntryFunction::BuildFileTypeInfo(
-    ui::SelectFileDialog::FileTypeInfo* file_type_info,
-    const base::FilePath::StringType& suggested_extension,
-    const AcceptOptions* accepts,
-    const bool* acceptsAllTypes) {
-  file_type_info->include_all_files = true;
-  if (acceptsAllTypes)
-    file_type_info->include_all_files = *acceptsAllTypes;
-
-  bool need_suggestion =
-      !file_type_info->include_all_files && !suggested_extension.empty();
-
-  if (accepts) {
-    for (const file_system::AcceptOption& option : *accepts) {
-      base::string16 description;
-      std::vector<base::FilePath::StringType> extensions;
-
-      if (!GetFileTypesFromAcceptOption(option, &extensions, &description))
-        continue;  // No extensions were found.
-
-      file_type_info->extensions.push_back(extensions);
-      file_type_info->extension_description_overrides.push_back(description);
-
-      // If we still need to find suggested_extension, hunt for it inside the
-      // extensions returned from GetFileTypesFromAcceptOption.
-      if (need_suggestion &&
-          base::ContainsValue(extensions, suggested_extension)) {
-        need_suggestion = false;
-      }
-    }
-  }
-
-  // If there's nothing in our accepted extension list or we couldn't find the
-  // suggested extension required, then default to accepting all types.
-  if (file_type_info->extensions.empty() || need_suggestion)
-    file_type_info->include_all_files = true;
-}
-
-void FileSystemChooseEntryFunction::BuildSuggestion(
-    const std::string* opt_name,
-    base::FilePath* suggested_name,
-    base::FilePath::StringType* suggested_extension) {
-  if (opt_name) {
-    *suggested_name = base::FilePath::FromUTF8Unsafe(*opt_name);
-
-    // Don't allow any path components; shorten to the base name. This should
-    // result in a relative path, but in some cases may not. Clear the
-    // suggestion for safety if this is the case.
-    *suggested_name = suggested_name->BaseName();
-    if (suggested_name->IsAbsolute())
-      *suggested_name = base::FilePath();
-
-    *suggested_extension = suggested_name->Extension();
-    if (!suggested_extension->empty())
-      suggested_extension->erase(suggested_extension->begin());  // drop the .
-  }
-}
-
-void FileSystemChooseEntryFunction::SetInitialPathAndShowPicker(
-    const base::FilePath& previous_path,
-    const base::FilePath& suggested_name,
-    const ui::SelectFileDialog::FileTypeInfo& file_type_info,
-    ui::SelectFileDialog::Type picker_type,
-    bool is_previous_path_directory) {
-  DCHECK_CURRENTLY_ON(content::BrowserThread::UI);
-  if (is_previous_path_directory) {
-    initial_path_ = previous_path.Append(suggested_name);
-  } else {
-    base::FilePath documents_dir;
-    if (PathService::Get(chrome::DIR_USER_DOCUMENTS, &documents_dir)) {
-      initial_path_ = documents_dir.Append(suggested_name);
-    } else {
-      initial_path_ = suggested_name;
-    }
-  }
-  ShowPicker(file_type_info, picker_type);
-}
-
-bool FileSystemChooseEntryFunction::RunAsync() {
-  std::unique_ptr<ChooseEntry::Params> params(
-      ChooseEntry::Params::Create(*args_));
-  EXTENSION_FUNCTION_VALIDATE(params.get());
-
-  base::FilePath suggested_name;
-  ui::SelectFileDialog::FileTypeInfo file_type_info;
-  ui::SelectFileDialog::Type picker_type =
-      ui::SelectFileDialog::SELECT_OPEN_FILE;
-
-  file_system::ChooseEntryOptions* options = params->options.get();
-  if (options) {
-    multiple_ = options->accepts_multiple && *options->accepts_multiple;
-    if (multiple_)
-      picker_type = ui::SelectFileDialog::SELECT_OPEN_MULTI_FILE;
-
-    if (options->type == file_system::CHOOSE_ENTRY_TYPE_OPENWRITABLEFILE &&
-        !app_file_handler_util::HasFileSystemWritePermission(
-            extension_.get())) {
-      error_ = kRequiresFileSystemWriteError;
-      return false;
-    } else if (options->type == file_system::CHOOSE_ENTRY_TYPE_SAVEFILE) {
-      if (!app_file_handler_util::HasFileSystemWritePermission(
-              extension_.get())) {
-        error_ = kRequiresFileSystemWriteError;
-        return false;
-      }
-      if (multiple_) {
-        error_ = kMultipleUnsupportedError;
-        return false;
-      }
-      picker_type = ui::SelectFileDialog::SELECT_SAVEAS_FILE;
-    } else if (options->type == file_system::CHOOSE_ENTRY_TYPE_OPENDIRECTORY) {
-      is_directory_ = true;
-      if (!extension_->permissions_data()->HasAPIPermission(
-              APIPermission::kFileSystemDirectory)) {
-        error_ = kRequiresFileSystemDirectoryError;
-        return false;
-      }
-      if (multiple_) {
-        error_ = kMultipleUnsupportedError;
-        return false;
-      }
-      picker_type = ui::SelectFileDialog::SELECT_FOLDER;
-    }
-
-    base::FilePath::StringType suggested_extension;
-    BuildSuggestion(options->suggested_name.get(), &suggested_name,
-                    &suggested_extension);
-
-    BuildFileTypeInfo(&file_type_info, suggested_extension,
-                      options->accepts.get(), options->accepts_all_types.get());
-  }
-
-  file_type_info.allowed_paths = ui::SelectFileDialog::FileTypeInfo::ANY_PATH;
-
-  base::FilePath previous_path = file_system_api::GetLastChooseEntryDirectory(
-      ExtensionPrefs::Get(GetProfile()), extension()->id());
-
-  if (previous_path.empty()) {
-    SetInitialPathAndShowPicker(previous_path, suggested_name, file_type_info,
-                                picker_type, false);
-    return true;
-  }
-
-  base::Callback<void(bool)> set_initial_path_callback = base::Bind(
-      &FileSystemChooseEntryFunction::SetInitialPathAndShowPicker, this,
-      previous_path, suggested_name, file_type_info, picker_type);
-
-// Check whether the |previous_path| is a non-native directory.
-#if defined(OS_CHROMEOS)
-  if (file_manager::util::IsUnderNonNativeLocalPath(GetProfile(),
-                                                    previous_path)) {
-    file_manager::util::IsNonNativeLocalPathDirectory(
-        GetProfile(), previous_path, set_initial_path_callback);
-    return true;
-  }
-#endif
-  base::PostTaskWithTraitsAndReplyWithResult(
-      FROM_HERE, {base::MayBlock(), base::TaskPriority::BACKGROUND},
-      base::Bind(&base::DirectoryExists, previous_path),
-      set_initial_path_callback);
-
-  return true;
-}
-
-bool FileSystemRetainEntryFunction::RunAsync() {
-  std::string entry_id;
-  EXTENSION_FUNCTION_VALIDATE(args_->GetString(0, &entry_id));
-  SavedFilesService* saved_files_service = SavedFilesService::Get(GetProfile());
-  // Add the file to the retain list if it is not already on there.
-  if (!saved_files_service->IsRegistered(extension_->id(), entry_id)) {
-    std::string filesystem_name;
-    std::string filesystem_path;
-    base::FilePath path;
-    EXTENSION_FUNCTION_VALIDATE(args_->GetString(1, &filesystem_name));
-    EXTENSION_FUNCTION_VALIDATE(args_->GetString(2, &filesystem_path));
-    if (!app_file_handler_util::ValidateFileEntryAndGetPath(
-            filesystem_name, filesystem_path,
-            render_frame_host()->GetProcess()->GetID(), &path, &error_)) {
-      return false;
-    }
-
-    std::string filesystem_id;
-    if (!storage::CrackIsolatedFileSystemName(filesystem_name, &filesystem_id))
-      return false;
-
-    const GURL site = util::GetSiteForExtensionId(extension_id(), GetProfile());
-    storage::FileSystemContext* const context =
-        content::BrowserContext::GetStoragePartitionForSite(GetProfile(), site)
-            ->GetFileSystemContext();
-    const storage::FileSystemURL url = context->CreateCrackedFileSystemURL(
-        site, storage::kFileSystemTypeIsolated,
-        IsolatedContext::GetInstance()
-            ->CreateVirtualRootPath(filesystem_id)
-            .Append(base::FilePath::FromUTF8Unsafe(filesystem_path)));
-
-    content::BrowserThread::PostTask(
-        content::BrowserThread::IO, FROM_HERE,
-        base::BindOnce(
-            base::IgnoreResult(
-                &storage::FileSystemOperationRunner::GetMetadata),
-            context->operation_runner()->AsWeakPtr(), url,
-            storage::FileSystemOperation::GET_METADATA_FIELD_IS_DIRECTORY,
-            base::Bind(
-                &PassFileInfoToUIThread,
-                base::Bind(&FileSystemRetainEntryFunction::RetainFileEntry,
-                           this, entry_id, path))));
-    return true;
-  }
-
-  saved_files_service->EnqueueFileEntry(extension_->id(), entry_id);
-  SendResponse(true);
-  return true;
-}
-
-void FileSystemRetainEntryFunction::RetainFileEntry(
-    const std::string& entry_id,
-    const base::FilePath& path,
-    std::unique_ptr<base::File::Info> file_info) {
-  if (!file_info) {
-    SendResponse(false);
-    return;
-  }
-
-  SavedFilesService* saved_files_service = SavedFilesService::Get(GetProfile());
-  saved_files_service->RegisterFileEntry(extension_->id(), entry_id, path,
-                                         file_info->is_directory);
-  saved_files_service->EnqueueFileEntry(extension_->id(), entry_id);
-  SendResponse(true);
-}
-
-ExtensionFunction::ResponseAction FileSystemIsRestorableFunction::Run() {
-  std::string entry_id;
-  EXTENSION_FUNCTION_VALIDATE(args_->GetString(0, &entry_id));
-  return RespondNow(OneArgument(base::MakeUnique<base::Value>(
-      SavedFilesService::Get(Profile::FromBrowserContext(browser_context()))
-          ->IsRegistered(extension_->id(), entry_id))));
-}
-
-bool FileSystemRestoreEntryFunction::RunAsync() {
-  std::string entry_id;
-  bool needs_new_entry;
-  EXTENSION_FUNCTION_VALIDATE(args_->GetString(0, &entry_id));
-  EXTENSION_FUNCTION_VALIDATE(args_->GetBoolean(1, &needs_new_entry));
-  const SavedFileEntry* file_entry =
-      SavedFilesService::Get(GetProfile())
-          ->GetFileEntry(extension_->id(), entry_id);
-  if (!file_entry) {
-    error_ = kUnknownIdError;
-    return false;
-  }
-
-  SavedFilesService::Get(GetProfile())
-      ->EnqueueFileEntry(extension_->id(), entry_id);
-
-  // Only create a new file entry if the renderer requests one.
-  // |needs_new_entry| will be false if the renderer already has an Entry for
-  // |entry_id|.
-  if (needs_new_entry) {
-    is_directory_ = file_entry->is_directory;
-    std::unique_ptr<base::DictionaryValue> result = CreateResult();
-    AddEntryToResult(file_entry->path, file_entry->id, result.get());
-    SetResult(std::move(result));
-  }
-  SendResponse(true);
-  return true;
-}
-
-ExtensionFunction::ResponseAction FileSystemObserveDirectoryFunction::Run() {
-  NOTIMPLEMENTED();
-  return RespondNow(Error(kUnknownIdError));
-}
-
-ExtensionFunction::ResponseAction FileSystemUnobserveEntryFunction::Run() {
-  NOTIMPLEMENTED();
-  return RespondNow(Error(kUnknownIdError));
-}
-
-ExtensionFunction::ResponseAction FileSystemGetObservedEntriesFunction::Run() {
-  NOTIMPLEMENTED();
-  return RespondNow(Error(kUnknownIdError));
-}
-
-#if !defined(OS_CHROMEOS)
-ExtensionFunction::ResponseAction FileSystemRequestFileSystemFunction::Run() {
-  using api::file_system::RequestFileSystem::Params;
-  const std::unique_ptr<Params> params(Params::Create(*args_));
-  EXTENSION_FUNCTION_VALIDATE(params);
-
-  NOTIMPLEMENTED();
-  return RespondNow(Error(kNotSupportedOnCurrentPlatformError));
-}
-
-ExtensionFunction::ResponseAction FileSystemGetVolumeListFunction::Run() {
-  NOTIMPLEMENTED();
-  return RespondNow(Error(kNotSupportedOnCurrentPlatformError));
-}
-#else
-
-FileSystemRequestFileSystemFunction::FileSystemRequestFileSystemFunction()
-    : chrome_details_(this) {}
-
-FileSystemRequestFileSystemFunction::~FileSystemRequestFileSystemFunction() {}
-
-ExtensionFunction::ResponseAction FileSystemRequestFileSystemFunction::Run() {
-  using api::file_system::RequestFileSystem::Params;
-  const std::unique_ptr<Params> params(Params::Create(*args_));
-  EXTENSION_FUNCTION_VALIDATE(params);
-
+bool ChromeFileSystemDelegate::IsGrantable(
+    content::BrowserContext* browser_context,
+    content::RenderFrameHost* render_frame_host,
+    const Extension& extension) {
   // Only kiosk apps in kiosk sessions can use this API.
   // Additionally it is enabled for whitelisted component extensions and apps.
-  file_system_api::ConsentProviderDelegate consent_provider_delegate(
-      chrome_details_.GetProfile(), render_frame_host());
-  file_system_api::ConsentProvider consent_provider(&consent_provider_delegate);
-
-  if (!consent_provider.IsGrantable(*extension()))
-    return RespondNow(Error(kNotSupportedOnNonKioskSessionError));
+  ConsentProviderDelegate consent_provider_delegate(
+      Profile::FromBrowserContext(browser_context));
+  return ConsentProvider(&consent_provider_delegate).IsGrantable(extension);
+}
+
+void ChromeFileSystemDelegate::RequestFileSystem(
+    content::BrowserContext* browser_context,
+    scoped_refptr<UIThreadExtensionFunction> requester,
+    const Extension& extension,
+    std::string volume_id,
+    bool writable,
+    const FileSystemCallback& success_callback,
+    const ErrorCallback& error_callback) {
+  ConsentProviderDelegate consent_provider_delegate(
+      Profile::FromBrowserContext(browser_context));
+  ConsentProvider consent_provider(&consent_provider_delegate);
+
+  if (!consent_provider.IsGrantable(extension)) {
+    error_callback.Run(kNotSupportedOnNonKioskSessionError);
+    return;
+  }
 
   using file_manager::VolumeManager;
   using file_manager::Volume;
-  VolumeManager* const volume_manager =
-      VolumeManager::Get(chrome_details_.GetProfile());
+  VolumeManager* const volume_manager = VolumeManager::Get(browser_context);
   DCHECK(volume_manager);
 
-  const bool writable =
-      params->options.writable.get() && *params->options.writable.get();
   if (writable &&
-      !app_file_handler_util::HasFileSystemWritePermission(extension_.get())) {
-    return RespondNow(Error(kRequiresFileSystemWriteError));
+      !app_file_handler_util::HasFileSystemWritePermission(&extension)) {
+    error_callback.Run(kRequiresFileSystemWriteError);
+    return;
   }
 
   base::WeakPtr<file_manager::Volume> volume =
-      volume_manager->FindVolumeById(params->options.volume_id);
-  if (!volume.get())
-    return RespondNow(Error(kVolumeNotFoundError));
+      volume_manager->FindVolumeById(volume_id);
+  if (!volume.get()) {
+    error_callback.Run(kVolumeNotFoundError);
+    return;
+  }
 
   const GURL site =
-      util::GetSiteForExtensionId(extension_id(), chrome_details_.GetProfile());
+      util::GetSiteForExtensionId(extension.id(), browser_context);
   scoped_refptr<storage::FileSystemContext> file_system_context =
-      content::BrowserContext::GetStoragePartitionForSite(
-          chrome_details_.GetProfile(), site)
+      content::BrowserContext::GetStoragePartitionForSite(browser_context, site)
           ->GetFileSystemContext();
   storage::ExternalFileSystemBackend* const backend =
       file_system_context->external_backend();
-  DCHECK(backend);
-
-  base::FilePath virtual_path;
-  if (!backend->GetVirtualPath(volume->mount_path(), &virtual_path))
-    return RespondNow(Error(kSecurityError));
-
-  if (writable && (volume->is_read_only()))
-    return RespondNow(Error(kSecurityError));
-
-  consent_provider.RequestConsent(
-      *extension(), volume, writable,
-      base::Bind(&FileSystemRequestFileSystemFunction::OnConsentReceived, this,
-                 volume, writable));
-  return RespondLater();
-}
-
-void FileSystemRequestFileSystemFunction::OnConsentReceived(
-    const base::WeakPtr<file_manager::Volume>& volume,
-    bool writable,
-    ConsentProvider::Consent result) {
-  using file_manager::VolumeManager;
-  using file_manager::Volume;
-
-  // Render frame host can be gone before this callback method is executed.
-  if (!render_frame_host()) {
-    Respond(Error(""));
-    return;
-  }
-
-  switch (result) {
-    case ConsentProvider::CONSENT_REJECTED:
-      Respond(Error(kSecurityError));
-      return;
-
-    case ConsentProvider::CONSENT_IMPOSSIBLE:
-      Respond(Error(kConsentImpossible));
-      return;
-
-    case ConsentProvider::CONSENT_GRANTED:
-      break;
-  }
-
-  if (!volume.get()) {
-    Respond(Error(kVolumeNotFoundError));
-    return;
-  }
-
-  const GURL site =
-      util::GetSiteForExtensionId(extension_id(), chrome_details_.GetProfile());
-  scoped_refptr<storage::FileSystemContext> file_system_context =
-      content::BrowserContext::GetStoragePartitionForSite(
-          chrome_details_.GetProfile(), site)
-          ->GetFileSystemContext();
-  storage::ExternalFileSystemBackend* const backend =
-      file_system_context->external_backend();
   DCHECK(backend);
 
   base::FilePath virtual_path;
   if (!backend->GetVirtualPath(volume->mount_path(), &virtual_path)) {
-    Respond(Error(kSecurityError));
+    error_callback.Run(kSecurityError);
     return;
   }
 
-  storage::IsolatedContext* const isolated_context =
-      storage::IsolatedContext::GetInstance();
-  DCHECK(isolated_context);
-
-  const storage::FileSystemURL original_url =
-      file_system_context->CreateCrackedFileSystemURL(
-          GURL(std::string(kExtensionScheme) + url::kStandardSchemeSeparator +
-               extension_id()),
-          storage::kFileSystemTypeExternal, virtual_path);
-
-  // Set a fixed register name, as the automatic one would leak the mount point
-  // directory.
-  std::string register_name = "fs";
-  const std::string file_system_id =
-      isolated_context->RegisterFileSystemForPath(
-          storage::kFileSystemTypeNativeForPlatformApp,
-          std::string() /* file_system_id */, original_url.path(),
-          &register_name);
-  if (file_system_id.empty()) {
-    Respond(Error(kSecurityError));
+  if (writable && (volume->is_read_only())) {
+    error_callback.Run(kSecurityError);
     return;
   }
 
-  backend->GrantFileAccessToExtension(extension_->id(), virtual_path);
+  const ConsentProvider::ConsentCallback& callback = base::Bind(
+      &OnConsentReceived, browser_context, requester, success_callback,
+      error_callback, extension.id(), volume, writable);
 
-  // Grant file permissions to the renderer hosting component.
-  content::ChildProcessSecurityPolicy* policy =
-      content::ChildProcessSecurityPolicy::GetInstance();
-  DCHECK(policy);
-
-  // Read-only permisisons.
-  policy->GrantReadFile(render_frame_host()->GetProcess()->GetID(),
-                        volume->mount_path());
-  policy->GrantReadFileSystem(render_frame_host()->GetProcess()->GetID(),
-                              file_system_id);
-
-  // Additional write permissions.
-  if (writable) {
-    policy->GrantCreateReadWriteFile(render_frame_host()->GetProcess()->GetID(),
-                                     volume->mount_path());
-    policy->GrantCopyInto(render_frame_host()->GetProcess()->GetID(),
-                          volume->mount_path());
-    policy->GrantWriteFileSystem(render_frame_host()->GetProcess()->GetID(),
-                                 file_system_id);
-    policy->GrantDeleteFromFileSystem(
-        render_frame_host()->GetProcess()->GetID(), file_system_id);
-    policy->GrantCreateFileForFileSystem(
-        render_frame_host()->GetProcess()->GetID(), file_system_id);
-  }
-
-  std::unique_ptr<base::DictionaryValue> dict(new base::DictionaryValue());
-  dict->SetString("file_system_id", file_system_id);
-  dict->SetString("file_system_path", register_name);
-
-  Respond(OneArgument(std::move(dict)));
+  consent_provider.RequestConsent(extension, requester->render_frame_host(),
+                                  volume, writable, callback);
 }
 
-FileSystemGetVolumeListFunction::FileSystemGetVolumeListFunction()
-    : chrome_details_(this) {}
+void ChromeFileSystemDelegate::GetVolumeList(
+    content::BrowserContext* browser_context,
+    const VolumeListCallback& success_callback,
+    const ErrorCallback& error_callback) {
+  std::vector<file_system::Volume> result_volume_list;
+  FillVolumeList(browser_context, &result_volume_list);
 
-FileSystemGetVolumeListFunction::~FileSystemGetVolumeListFunction() {}
+  success_callback.Run(result_volume_list);
+}
 
-ExtensionFunction::ResponseAction FileSystemGetVolumeListFunction::Run() {
-  // Only kiosk apps in kiosk sessions can use this API.
-  // Additionally it is enabled for whitelisted component extensions and apps.
-  file_system_api::ConsentProviderDelegate consent_provider_delegate(
-      chrome_details_.GetProfile(), render_frame_host());
-  file_system_api::ConsentProvider consent_provider(&consent_provider_delegate);
+#endif  // defined(OS_CHROMEOS)
 
-  if (!consent_provider.IsGrantable(*extension()))
-    return RespondNow(Error(kNotSupportedOnNonKioskSessionError));
-  std::vector<api::file_system::Volume> result_volume_list;
-  FillVolumeList(chrome_details_.GetProfile(), &result_volume_list);
-
-  return RespondNow(ArgumentList(
-      api::file_system::GetVolumeList::Results::Create(result_volume_list)));
+SavedFilesServiceInterface* ChromeFileSystemDelegate::GetSavedFilesService(
+    content::BrowserContext* browser_context) {
+  return apps::SavedFilesService::Get(browser_context);
 }
-#endif
 
 }  // namespace extensions