(Sorry, I don't understand how that CL is related to _fuchsia.)

But I'll fix that here, thanks for noticing https://cs.chromium.org/chromium/src/build/config/clang/BUILD.gn?rcl=8761b7bf600539b8e4ec8fb08d642a547af5815d&l=14

Clipboard fail, sorry. https://chromium-review.googlesource.com/c/chromium/src/+/735620 is what I meant.

thakis: Thanks for spotting that!
scottmg: Thanks for taking care of this; let me know if you find there's a lot to clean up to get this to land...

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/8aba4fd3e19fa80cce7fcf5803774781d17642b8

commit 8aba4fd3e19fa80cce7fcf5803774781d17642b8
Author: Nico Weber <thakis@chromium.org>
Date: Tue Oct 24 15:58:29 2017

Make style plugin and oilpan plugin work in win/cross builds.

Which plugin shared library to load needs to check the host os, not the
target one.

This change also exposed that we weren't using plugin and oilpan
plugins in Fuchsia builds. The Fuchsia code isn't style-plugin clean,
so explicitly disable the style plugin in Fuchsia builds for now and
add a TODO for enabling it there.

Bug: 495204, 777847 
Change-Id: I39b00244581673fbb2e90f335ce561159ff4a590
Reviewed-on: https://chromium-review.googlesource.com/735620
Reviewed-by: Daniel Cheng <dcheng@chromium.org>
Commit-Queue: Nico Weber <thakis@chromium.org>
Cr-Commit-Position: refs/heads/master@{#511167}
[modify] https://crrev.com/8aba4fd3e19fa80cce7fcf5803774781d17642b8/build/config/clang/BUILD.gn
[modify] https://crrev.com/8aba4fd3e19fa80cce7fcf5803774781d17642b8/third_party/WebKit/Source/BUILD.gn

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/80380845ecfde4c1e93f27de381fab0aa3ea84b7

commit 80380845ecfde4c1e93f27de381fab0aa3ea84b7
Author: Scott Graham <scottmg@chromium.org>
Date: Wed Oct 25 04:01:02 2017

Enable chromium-style clang plugin on Fuchsia

Bug:  777847 
Change-Id: Id237b07d559dc88605773607e681ab8fbb9991f2
Reviewed-on: https://chromium-review.googlesource.com/734878
Reviewed-by: Nico Weber <thakis@chromium.org>
Commit-Queue: Scott Graham <scottmg@chromium.org>
Cr-Commit-Position: refs/heads/master@{#511360}
[modify] https://crrev.com/80380845ecfde4c1e93f27de381fab0aa3ea84b7/base/message_loop/message_pump_fuchsia.cc
[modify] https://crrev.com/80380845ecfde4c1e93f27de381fab0aa3ea84b7/base/message_loop/message_pump_fuchsia.h
[modify] https://crrev.com/80380845ecfde4c1e93f27de381fab0aa3ea84b7/build/config/clang/BUILD.gn