GitLab

Remove deprecated_default_sources_assignment_filter and replace
it with explicit is_win, is_mac, etc. sections.

Bug: 1018739
Change-Id: Id133ab0b0744c07405d0ed69eb9774b27b5c09f0
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2442540
Auto-Submit: Sylvain Defresne <sdefresne@chromium.org>
Commit-Queue: Avi Drissman <avi@chromium.org>
Reviewed-by: Avi Drissman <avi@chromium.org>
Cr-Commit-Position: refs/heads/master@{#812827}