Make the default ctor of rtc::Thread, protected

Make the default ctor of rtc::Thread, protected.
The goal is to force use of Thread::Create or Thread::CreateWithSocketServer.

The default constructor constructs a 'default' socket server, which is usually a 'physical' socket server, but not always. Not every instance of Thread actually needs to have network support, so it's better to have this be explicit instead of unknowingly instantiate one.

BUG=none

Review-Url: https://codereview.webrtc.org/2981623002
Cr-Commit-Position: refs/heads/master@{#19001}
Committed: https://chromium.googlesource.com/external/webrtc/+/a8a351599788f346a2265cfcd3da9a06f577de7f

[tommi, 2017-07-12 12:28:12]

The CQ bit was checked by tommi@webrtc.org to run a CQ dry run

[commit-bot: I haz the power, 2017-07-12 12:28:14]

Dry run: CQ is trying da patch.

Follow status at:
https://chromium-cq-status.appspot.com/v2/patch-status/codereview.webrtc.org/...

[commit-bot: I haz the power, 2017-07-12 12:55:04]

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

[commit-bot: I haz the power, 2017-07-12 12:55:04]

Dry run: Try jobs failed on following builders:
  android_compile_x86_rel on master.tryserver.webrtc (JOB_FAILED,
http://build.chromium.org/p/tryserver.webrtc/builders/android_compile_x86_rel...)

[tommi, 2017-07-12 13:15:06]

Android

[tommi, 2017-07-12 13:16:36]

Format

[tommi, 2017-07-12 15:49:37]

Description was changed from

==========
Make the default ctor of rtc::Thread, protected

BUG=none
==========

to

==========
Make the default ctor of rtc::Thread, protected.
The goal is to force use of Thread::Create or Thread::CreateWithSocketServer.

The default constructor constructs a 'default' socket server, which is usually a
'physical' socket server, but not always. Not every instance of Thread actually
needs to have network support, so it's better to have this be explicit instead
of unknowingly instantiate one.

BUG=none
==========

[tommi, 2017-07-12 15:49:49]

tommi@webrtc.org changed reviewers:
+ kthelgason@webrtc.org

[tommi, 2017-07-12 15:49:59]

The CQ bit was checked by tommi@webrtc.org to run a CQ dry run

[commit-bot: I haz the power, 2017-07-12 15:50:07]

Dry run: CQ is trying da patch.

Follow status at:
https://chromium-cq-status.appspot.com/v2/patch-status/codereview.webrtc.org/...

[commit-bot: I haz the power, 2017-07-12 17:50:33]

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

[commit-bot: I haz the power, 2017-07-12 17:50:34]

Dry run: Try jobs failed on following builders:
  win_clang_dbg on master.tryserver.webrtc (JOB_TIMED_OUT, build has not started
yet; builder either lacks capacity or does not exist (misspelled?))
  win_clang_rel on master.tryserver.webrtc (JOB_TIMED_OUT, build has not started
yet; builder either lacks capacity or does not exist (misspelled?))
  win_dbg on master.tryserver.webrtc (JOB_TIMED_OUT, build has not started yet;
builder either lacks capacity or does not exist (misspelled?))
  win_rel on master.tryserver.webrtc (JOB_TIMED_OUT, build has not started yet;
builder either lacks capacity or does not exist (misspelled?))
  win_x64_clang_dbg on master.tryserver.webrtc (JOB_TIMED_OUT, build has not
started yet; builder either lacks capacity or does not exist (misspelled?))
  win_x64_clang_rel on master.tryserver.webrtc (JOB_TIMED_OUT, build has not
started yet; builder either lacks capacity or does not exist (misspelled?))
  win_x64_dbg on master.tryserver.webrtc (JOB_TIMED_OUT, build has not started
yet; builder either lacks capacity or does not exist (misspelled?))
  win_x64_rel on master.tryserver.webrtc (JOB_TIMED_OUT, build has not started
yet; builder either lacks capacity or does not exist (misspelled?))

[kthelgason, 2017-07-13 12:30:31]

lgtm!

[tommi, 2017-07-13 12:44:05]

The CQ bit was checked by tommi@webrtc.org

[commit-bot: I haz the power, 2017-07-13 12:44:10]

CQ is trying da patch.

Follow status at:
https://chromium-cq-status.appspot.com/v2/patch-status/codereview.webrtc.org/...

[commit-bot: I haz the power, 2017-07-13 12:47:25]

CQ is committing da patch.

Bot data: {"patchset_id": 40001, "attempt_start_ts": 1499949845448550,
"parent_rev": "abcf112ae0e040f94953e20bec86574f18d5a508", "commit_rev":
"a8a351599788f346a2265cfcd3da9a06f577de7f"}

[commit-bot: I haz the power, 2017-07-13 12:47:32]

Description was changed from

==========
Make the default ctor of rtc::Thread, protected.
The goal is to force use of Thread::Create or Thread::CreateWithSocketServer.

The default constructor constructs a 'default' socket server, which is usually a
'physical' socket server, but not always. Not every instance of Thread actually
needs to have network support, so it's better to have this be explicit instead
of unknowingly instantiate one.

BUG=none
==========

to

==========
Make the default ctor of rtc::Thread, protected.
The goal is to force use of Thread::Create or Thread::CreateWithSocketServer.

The default constructor constructs a 'default' socket server, which is usually a
'physical' socket server, but not always. Not every instance of Thread actually
needs to have network support, so it's better to have this be explicit instead
of unknowingly instantiate one.

BUG=none

Review-Url: https://codereview.webrtc.org/2981623002
Cr-Commit-Position: refs/heads/master@{#19001}
Committed:
https://chromium.googlesource.com/external/webrtc/+/a8a351599788f346a2265cfcd...
==========

[commit-bot: I haz the power, 2017-07-13 12:47:35]

Committed patchset #3 (id:40001) as
https://chromium.googlesource.com/external/webrtc/+/a8a351599788f346a2265cfcd...

[charujain, 2017-07-13 14:06:22]

A revert of this CL (patchset #3 id:40001) has been created in
https://codereview.webrtc.org/2979963002/ by charujain@webrtc.org.

The reason for reverting is: Break projects..