Remove MessageLoop destruction observer from mojo::Watcher.

Remove MessageLoop destruction observer from mojo::Watcher.

This CL is based on fdoray's CL http://crrev.com/2475273003
The only difference is this CL adds a message loop destruction observer for the
Java watcher implementation, in order to preserve its original behavior.

BUG=604762
Committed: https://crrev.com/1bd2370149a46bae21fecf9e98842ff51e8f5299
Cr-Commit-Position: refs/heads/master@{#435432}

[yzshen1, 2016-11-30 00:58:46]

The CQ bit was checked by yzshen@chromium.org to run a CQ dry run

[commit-bot: I haz the power, 2016-11-30 00:59:39]

Dry run: CQ is trying da patch. Follow status at
 
https://chromium-cq-status.appspot.com/v2/patch-status/codereview.chromium.or...

[yzshen1, 2016-11-30 01:05:08]

The CQ bit was checked by yzshen@chromium.org to run a CQ dry run

[commit-bot: I haz the power, 2016-11-30 01:05:40]

Dry run: CQ is trying da patch. Follow status at
 
https://chromium-cq-status.appspot.com/v2/patch-status/codereview.chromium.or...

[yzshen1, 2016-11-30 01:11:21]

yzshen@chromium.org changed reviewers:
+ rockot@chromium.org

[yzshen1, 2016-11-30 01:11:22]

Hi, Ken.

Would you please take a look? Thanks!

[commit-bot: I haz the power, 2016-11-30 03:07:32]

The CQ bit was unchecked by commit-bot@chromium.org

[commit-bot: I haz the power, 2016-11-30 03:07:33]

Dry run: Try jobs failed on following builders:
  blimp_linux_dbg on master.tryserver.chromium.linux (JOB_TIMED_OUT, no build
URL)
  cast_shell_linux on master.tryserver.chromium.linux (JOB_TIMED_OUT, no build
URL)
  chromeos_amd64-generic_chromium_compile_only_ng on
master.tryserver.chromium.linux (JOB_TIMED_OUT, no build URL)
  chromeos_daisy_chromium_compile_only_ng on master.tryserver.chromium.linux
(JOB_TIMED_OUT, no build URL)
  chromeos_x86-generic_chromium_compile_only_ng on
master.tryserver.chromium.linux (JOB_TIMED_OUT, no build URL)
  linux_chromium_asan_rel_ng on master.tryserver.chromium.linux (JOB_TIMED_OUT,
no build URL)
  linux_chromium_chromeos_compile_dbg_ng on master.tryserver.chromium.linux
(JOB_TIMED_OUT, no build URL)
  linux_chromium_chromeos_ozone_rel_ng on master.tryserver.chromium.linux
(JOB_TIMED_OUT, no build URL)
  linux_chromium_chromeos_rel_ng on master.tryserver.chromium.linux
(JOB_TIMED_OUT, no build URL)
  linux_chromium_clobber_rel_ng on master.tryserver.chromium.linux
(JOB_TIMED_OUT, no build URL)
  linux_chromium_compile_dbg_ng on master.tryserver.chromium.linux
(JOB_TIMED_OUT, no build URL)
  linux_chromium_rel_ng on master.tryserver.chromium.linux (JOB_TIMED_OUT, no
build URL)

[Ken Rockot(use gerrit already), 2016-11-30 19:21:40]

lgtm

[yzshen1, 2016-11-30 19:27:45]

The CQ bit was checked by yzshen@chromium.org

[commit-bot: I haz the power, 2016-11-30 19:28:51]

CQ is trying da patch. Follow status at
 
https://chromium-cq-status.appspot.com/v2/patch-status/codereview.chromium.or...

[commit-bot: I haz the power, 2016-11-30 21:54:56]

CQ is committing da patch.

Bot data: {"patchset_id": 20001, "attempt_start_ts": 1480534065993820,
"parent_rev": "a248cfc4f5c2c0b906bc9afe744b8df7c9791708", "commit_rev":
"9ea152e3cbadd1b3976f5c0cc8d14b0e570f02ea"}

[commit-bot: I haz the power, 2016-11-30 21:55:25]

Committed patchset #2 (id:20001)

[commit-bot: I haz the power, 2016-11-30 21:59:09]

Description was changed from

==========
Remove MessageLoop destruction observer from mojo::Watcher.

This CL is based on fdoray's CL http://crrev.com/2475273003
The only difference is this CL adds a message loop destruction observer for the
Java watcher implementation, in order to preserve its original behavior.

BUG=604762
==========

to

==========
Remove MessageLoop destruction observer from mojo::Watcher.

This CL is based on fdoray's CL http://crrev.com/2475273003
The only difference is this CL adds a message loop destruction observer for the
Java watcher implementation, in order to preserve its original behavior.

BUG=604762

Committed: https://crrev.com/1bd2370149a46bae21fecf9e98842ff51e8f5299
Cr-Commit-Position: refs/heads/master@{#435432}
==========

[commit-bot: I haz the power, 2016-11-30 21:59:10]

Patchset 2 (id:??) landed as
https://crrev.com/1bd2370149a46bae21fecf9e98842ff51e8f5299
Cr-Commit-Position: refs/heads/master@{#435432}