I'm not sure that I've ever had something to do w/ this particular file; regardless, it's probably better to have the Chromoting folks triage this ...

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/73b6e8740d40deefa0ee829325c88028f4cdbb6a

commit 73b6e8740d40deefa0ee829325c88028f4cdbb6a
Author: Zijie He <zijiehe@chromium.org>
Date: Wed Nov 01 17:43:26 2017

[Chromoting] Use shutil.move instead of os.rename to avoid "file already exists" error

This looks like a very common issue when using os.rename() on Windows.
https://www.google.com/search?q=python+os.rename+cannot+create+a+file+when+that+file+already+exists&oq=python+os.rename+cannot+create+a+file+when&aqs=chrome.0.0j69i57.12521j0j7&sourceid=chrome&ie=UTF-8

Bug: chromium:778370
Change-Id: I7132a2614fe9361c6860ae9598e994d7dbd00c5b
Reviewed-on: https://chromium-review.googlesource.com/748306
Reviewed-by: Jamie Walch <jamiewalch@chromium.org>
Commit-Queue: Zijie He <zijiehe@chromium.org>
Cr-Commit-Position: refs/heads/master@{#513172}
[modify] https://crrev.com/73b6e8740d40deefa0ee829325c88028f4cdbb6a/remoting/webapp/build-webapp.py

 Issue 780554  has been merged into this issue.

I rebased to 6804a845f099810c3f858a28a22e753a63d5d19e (r514150) and I just encountered this with my build. This doesn't seem to be fixed.

Interesting. I will have another look. Before that, does the build error look exactly the same?

Yep. I see:

PS C:\src\chrome\src> ninja -C out/debug all -j 300
ninja: Entering directory `out/debug'
[1/1] Regenerating ninja files
[11934/47502] ACTION //remoting/webapp:webapp(//build/toolchain/win:win_clang_x64)
FAILED: remoting-webapp.v2.zip
C:/python_27_amd64/files/python.exe ../../remoting/webapp/build-webapp.py Dev 64.0.3261.0 remoting/remoting-webapp.v2 remoting-webapp.v2.zip ../../remoting/webapp/crd/manifest.json.jinja2 --files_listfile gen/remoting/webapp/webapp_files.txt --locales_listfile gen/remoting/webapp/webapp_locales.txt --use_gcd 0
Traceback (most recent call last):
  File "../../remoting/webapp/build-webapp.py", line 380, in <module>
    sys.exit(main())
  File "../../remoting/webapp/build-webapp.py", line 376, in main
    return buildWebApp(**vars(args))
  File "../../remoting/webapp/build-webapp.py", line 232, in buildWebApp
    replaceString(destination, 'OAUTH2_API_BASE_URL', oauth2ApiBaseUrl)
  File "../../remoting/webapp/build-webapp.py", line 63, in replaceString
    "'" + placeholder + "'", "'" + value + "'")
  File "../../remoting/webapp/build-webapp.py", line 41, in findAndReplace
    shutil.move(filepath, oldFilepath)
  File "C:\python_27_amd64\files\lib\shutil.py", line 299, in move
    copy2(src, real_dst)
  File "C:\python_27_amd64\files\lib\shutil.py", line 128, in copy2
    copyfile(src, dst)
  File "C:\python_27_amd64\files\lib\shutil.py", line 83, in copyfile
    with open(dst, 'wb') as fdst:
IOError: [Errno 13] Permission denied: 'remoting/remoting-webapp.v2\\plugin_settings.js.old'
[12233/47502] CXX obj/v8/v8_base/simd-scalar-lowering.obj
ninja: build stopped: subcommand failed.
PS C:\src\chrome\src> git log
commit 6804a845f099810c3f858a28a22e753a63d5d19e (HEAD, origin/master, origin/HEAD)

This issue has been Available for over a year. If it's no longer important or seems unlikely to be fixed, please consider closing it out. If it is important, please re-triage the issue.

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