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=jbudorick@chromium.org

Bug: 714018
Change-Id: I2dc7e10e53b85661d646a0c2abb429eb05a9abcf
Reviewed-on: https://chromium-review.googlesource.com/c/1475638
Auto-Submit: kylechar <kylechar@chromium.org>
Reviewed-by: John Budorick <jbudorick@chromium.org>
Commit-Queue: John Budorick <jbudorick@chromium.org>
Cr-Original-Commit-Position: refs/heads/master@{#632671}
Cr-Mirrored-From: https://chromium.googlesource.com/chromium/src
Cr-Mirrored-Commit: 3467bd35c6cf6ba74233aa197447d1bab82439b4
7 files changed