GitLab

MessageLoop::PostTask/PostDelayedTask/DeleteSoon/ReleaseSoon
are deprecated. This CL makes the following replacements to
remove some uses of these methods:

"MessageLoop::current()->PostTask" ->
  "ThreadTaskRunnerHandle::Get()->PostTask"
"MessageLoop::current()->PostDelayedTask" ->
  "ThreadTaskRunnerHandle::Get()->PostDelayedTask"
"MessageLoop::current()->DeleteSoon" ->
  "ThreadTaskRunnerHandle::Get()->DeleteSoon"
"MessageLoop::current()->ReleaseSoon" ->
  "ThreadTaskRunnerHandle::Get()->ReleaseSoon"

In files where these replacements are made, it adds these includes:
  #include "base/location.h"
  #include "base/single_thread_task_runner.h"
  #include "base/threading/thread_task_runner_handle.h"

And removes this include if it is no longer required:
  #include "base/message_loop/message_loop.h"

Why ThreadTaskRunnerHandle::Get() instead of
MessageLoop::current()->task_runner()?
 - The two are equivalent on threads that run a MessageLoop.
 - MessageLoop::current() doesn't work in base/task_scheduler
   because the scheduler's thread don't run MessageLoops.
   This CL will therefore facilitate the migration of browser
   threads to base/task_scheduler.

Steps to generate this patch:
1. Run message_loop_cleanup.py (see code on the bug).
2. Run tools/sort-headers.py on modified files.
3. Run git cl format.

BUG=616447
R=shess@chromium.org

Review-Url: https://codereview.chromium.org/2033693004
Cr-Commit-Position: refs/heads/master@{#398284}