Move "global properties" to ResourceFetcherProperties, part 3

This CL introduces ResourceFetcherProperties::IsDetached.
FetchContext::IsDetached remains, but it is no longer public.

Change-Id: I54f4515929fe497719a5ac8791ea7c5e6c922a64
Bug: 914739
Reviewed-on: https://chromium-review.googlesource.com/c/1406728
Commit-Queue: Yutaka Hirano <yhirano@chromium.org>
Reviewed-by: Hiroshige Hayashizaki <hiroshige@chromium.org>
Reviewed-by: Hiroki Nakagawa <nhiroki@chromium.org>
Cr-Commit-Position: refs/heads/master@{#623276}
8 files changed