Use base::BindOnce for PostTask callbacks.

TaskRunner::PostTask() takes a OnceCallback. Replace usage of
base::Bind(), which produces a RepeatingCallback, with base::BindOnce()
when the callback is created as a temporary inside of PostTask(). The
following regex was used to find instances that could be replaced:

(Post(?:Delayed)?Task)\((?:\n\s*)?FROM_HERE,(?:\n)?\s*base::Bind\(

Also replace any usage of base::Passed(&var) with std::move(var) for
variables passed to base::BindOnce(). base::Passed() isn't needed for
move-only types with OnceCallbacks.

This CL was uploaded by git cl split.

R=rockot@google.com

Bug: 714018
Change-Id: I6d57907a3aa4886b00851416b9ea002a39c9c5f9
Reviewed-on: https://chromium-review.googlesource.com/c/1475639
Auto-Submit: kylechar <kylechar@chromium.org>
Commit-Queue: Ken Rockot <rockot@google.com>
Reviewed-by: Ken Rockot <rockot@google.com>
Cr-Commit-Position: refs/heads/master@{#633762}
13 files changed