Cleanup: deprecate URLLoaderFactory::SetDefaultFactory()

The method's not really needed (and in AppCache cases used
wrongly after crrev.com/c/1371310) so removing it.

Bug: 887109
Change-Id: I5dfc7bfe8739178f951f96de221ab97d63c5d0cc
Reviewed-on: https://chromium-review.googlesource.com/c/1388131
Reviewed-by: Hiroki Nakagawa <[email protected]>
Commit-Queue: Kinuko Yasuda <[email protected]>
Cr-Commit-Position: refs/heads/master@{#618481}
6 files changed