GitLab

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

Bug: 1018739
Change-Id: I475d54b703c2cea4ca5f6a816a200511571901e3
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2445933Reviewed-by: Xiaohan Wang <xhwang@chromium.org>
Commit-Queue: Sylvain Defresne <sdefresne@chromium.org>
Cr-Commit-Position: refs/heads/master@{#814156}