GitLab

Add JS module generation for:
//ui/file_manager/externs/background_window.js

Add the method forceFileOperationErrorForTest() in the interface
FileBrowserBackgroundFull and to its implementation
FileBrowserBackgroundFullImpl.  This is a preparation to run as JS
modules and as SWA; to avoid the integration test harness to reach to
global namespace `fileOperationUtil`.

Bug: 1133186
Change-Id: Ic5e2d38762b030c827c887021e7e611ba846228d
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2537285
Auto-Submit: Luciano Pacheco <lucmult@chromium.org>
Reviewed-by: Jeremie Boulic <jboulic@chromium.org>
Commit-Queue: Jeremie Boulic <jboulic@chromium.org>
Cr-Commit-Position: refs/heads/master@{#827714}