Add ChannelPosix::ResetSafely() to deal with a lingering crash

Add ChannelPosix::ResetSafely() to deal with a lingering crash

The CL [1] tightened the error check too much and revealed
an existing inconsistency and resulted a production crash.
This CL makes a workaround to that crash, turning a PCHECK()
to DPCHECK().

This is the second attempt. The first one was reverted at [2]

[1] https://crrev.com/ce44fef5fd60dd2be5c587d4b084bdcd36adcee4
[2] https://crrev.com/b83c03c7b691914a054abaab13fb9131b4e0152b

BUG=449233, 448245
R=agl@chromium.org,jam@chromium.org

Committed: https://crrev.com/cf3eae19b456536c5ff8dacf8800ec09f9af4bca
Cr-Commit-Position: refs/heads/master@{#313188}

Committed: https://crrev.com/2ad0be41e3029cfc6c1c5a8068d6d0873aa3871c
Cr-Commit-Position: refs/heads/master@{#313334}

[agl, 2015-01-27 00:38:39]

LGTM for addressing the crash, although it would be nice to address the existing
issue that was uncovered by the stricter check.

[Hajime Morrita, 2015-01-27 01:13:56]

On 2015/01/27 00:38:39, agl wrote:
> LGTM for addressing the crash, although it would be nice to address the
existing
> issue that was uncovered by the stricter check.

Yeah, I won't close the bug.
I have to learn Android specific bit of file passing to attack this.

[Hajime Morrita, 2015-01-27 01:14:00]

The CQ bit was checked by morrita@chromium.org

[commit-bot: I haz the power, 2015-01-27 01:15:36]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/882543002/1

[commit-bot: I haz the power, 2015-01-27 01:20:40]

Committed patchset #1 (id:1)

[commit-bot: I haz the power, 2015-01-27 01:21:32]

Patchset 1 (id:??) landed as
https://crrev.com/cf3eae19b456536c5ff8dacf8800ec09f9af4bca
Cr-Commit-Position: refs/heads/master@{#313188}

[yoichio, 2015-01-27 04:15:05]

A revert of this CL (patchset #1 id:1) has been created in
https://codereview.chromium.org/878843002/ by yoichio@chromium.org.

The reason for reverting is: many ipc test failed.
https://build.chromium.org/p/chromium.memory/builders/Linux%20ASan%20LSan%20T....

[Hajime Morrita, 2015-01-27 18:58:03]

DCHECK() has a side effect :-(
Having a fix, will land soon.

[Hajime Morrita, 2015-01-27 19:01:47]

The CQ bit was checked by morrita@chromium.org

[commit-bot: I haz the power, 2015-01-27 19:02:28]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/882543002/20001

[commit-bot: I haz the power, 2015-01-27 20:06:23]

Committed patchset #2 (id:20001)

[commit-bot: I haz the power, 2015-01-27 20:07:41]

Patchset 2 (id:??) landed as
https://crrev.com/2ad0be41e3029cfc6c1c5a8068d6d0873aa3871c
Cr-Commit-Position: refs/heads/master@{#313334}