[base] Small base::span Cleanups

This change replaces some usages of container.size() with the more
generic base::size(container) and introduces a overload for
base::make_span taking another span. This can be useful for template
code where make_span is invoked on an arbitrary container. Passing a
base::span to code like this should not result in a compilation failure.

Bug: 828324
Change-Id: Icd6e8269689cf9d9b663b6a916e73e232350785a
Reviewed-on: https://chromium-review.googlesource.com/1021381
Reviewed-by: Daniel Cheng <dcheng@chromium.org>
Commit-Queue: Jan Wilken Dörrie <jdoerrie@chromium.org>
Cr-Commit-Position: refs/heads/master@{#552415}

CrOS-Libchrome-Original-Commit: 5f892435ba416ae9ec9c7b39506742697e86f5f3
2 files changed
tree: f8b324cebaea3dd598c0ada556248255e43f7c1c
  1. base/
  2. build/
  3. components/
  4. dbus/
  5. device/
  6. ipc/
  7. mojo/
  8. testing/
  9. third_party/
  10. ui/