Revert of Build: Don't pass /GL to Clang on Windows (patchset #3 id:40001 of https://codereview.chromium.org/1186743002/)

Reason for revert:
Broke some official builds (http://crbug.com/500393). Will roll clang forward instead.

Original issue's description:
> Build: Don't pass /GL to Clang on Windows
>
> Windows Clang's support for LTO isn't ready to take on Chrome yet.
>
> BUG=82385
> R=thakis@chromium.org
> TBR=scottmg
>
> Committed: https://chromium.googlesource.com/chromium/src/+/4e76e7926ee51bdfdd635437920f455ae6444912

TBR=scottmg@chromium.org,hans@chromium.org
NOPRESUBMIT=true
NOTREECHECKS=true
NOTRY=true
BUG=82385

Review URL: https://codereview.chromium.org/1185133004

Cr-Commit-Position: refs/heads/master@{#334419}
2 files changed