GitLab

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

Bug: 1018739
Change-Id: I8f6218da609139d1edb24b56f782bbd0eb12d1eb
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2445413Reviewed-by: Peter Beverloo <peter@chromium.org>
Commit-Queue: Sylvain Defresne <sdefresne@chromium.org>
Cr-Commit-Position: refs/heads/master@{#813710}