Mojo: Add the ability to notify a Mojo Channel that it's going to be destroyed soon.

Mojo: Add the ability to notify a Mojo Channel that it's going to be destroyed soon.

* The actual destruction will typically happen on a different thread.
* We'd like to suppress warnings about the OS "pipe" being broken (which
  it often will, because we kill processes rather than shut them down).
* We'd like to know if we're still sending stuff on the channel even
  though it's about to go away.

R=yzshen@chromium.org, sky@chromium.org

Committed: https://src.chromium.org/viewvc/chrome?view=rev&revision=289531

[viettrungluu, 2014-08-13 19:24:30]

yzshen -> mojo/...
sky -> content/browser/...

[yzshen1, 2014-08-13 19:44:10]

LGTM with one nit

https://codereview.chromium.org/472603002/diff/1/mojo/embedder/channel_init.h
File mojo/embedder/channel_init.h (right):

https://codereview.chromium.org/472603002/diff/1/mojo/embedder/channel_init.h...
mojo/embedder/channel_init.h:43: // Invoked on the main thread once the channel
has been established. (This is
nit: maybe it is good to clarify what main thread means here? (the single thread
that this object is used on)

[viettrungluu, 2014-08-13 19:51:24]

Thanks.

On 2014/08/13 19:44:10, yzshen1 wrote:
> LGTM with one nit
> 
> https://codereview.chromium.org/472603002/diff/1/mojo/embedder/channel_init.h
> File mojo/embedder/channel_init.h (right):
> 
>
https://codereview.chromium.org/472603002/diff/1/mojo/embedder/channel_init.h...
> mojo/embedder/channel_init.h:43: // Invoked on the main thread once the
channel
> has been established. (This is
> nit: maybe it is good to clarify what main thread means here? (the single
thread
> that this object is used on)

Done.

[sky, 2014-08-13 20:06:30]

This seems dubious and error prone, but ok. LGTM

[viettrungluu, 2014-08-14 04:09:37]

The CQ bit was checked by viettrungluu@chromium.org

[commit-bot: I haz the power, 2014-08-14 04:14:07]

CQ is trying da patch. Follow status at

https://chromium-status.appspot.com/cq/viettrungluu@chromium.org/472603002/20001

[commit-bot: I haz the power, 2014-08-14 10:19:16]

FYI, CQ is re-trying this CL (attempt #1).
The failing builders are:
  linux_chromium_chromeos_rel_swarming on tryserver.chromium.linux
(http://build.chromium.org/p/tryserver.chromium.linux/builders/linux_chromium_...)
  win_chromium_x64_rel on tryserver.chromium.win
(http://build.chromium.org/p/tryserver.chromium.win/builders/win_chromium_x64_...)

[commit-bot: I haz the power, 2014-08-14 12:13:27]

Committed patchset #2 (20001) as 289531