Introduce apps API target in //apps and move app.runtime API into it

chrome/browser/extensions/api/file_system/file_system_api.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/api/file_system/file_system_api.h"
 
 #include "apps/app_window.h"
 #include "apps/app_window_registry.h"
+#include "apps/browser/file_handler_util.h"
 #include "apps/saved_files_service.h"
 #include "base/bind.h"
 #include "base/file_util.h"
 #include "base/files/file_path.h"
 #include "base/logging.h"
 #include "base/path_service.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"
@@ skipping 296 matching lines @@
   base::ListValue* list = new base::ListValue();
   response_->Set("entries", list);
   response_->SetBoolean("multiple", multiple_);
   SetResult(response_);
 }
 
 void FileSystemEntryFunction::AddEntryToResponse(
     const base::FilePath& path,
     const std::string& id_override) {
   DCHECK(response_);
-  extensions::app_file_handler_util::GrantedFileEntry file_entry =
+  apps::file_handler_util::GrantedFileEntry file_entry =
       extensions::app_file_handler_util::CreateFileEntry(
           GetProfile(),
           GetExtension(),
           render_view_host_->GetProcess()->GetID(),
           path,
           is_directory_);
   base::ListValue* entries;
   bool success = response_->GetList("entries", &entries);
   DCHECK(success);
 
@@ skipping 641 matching lines @@
   if (needs_new_entry) {
     is_directory_ = file_entry->is_directory;
     CreateResponse();
     AddEntryToResponse(file_entry->path, file_entry->id);
   }
   SendResponse(true);
   return true;
 }
 
 }  // namespace extensions