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

Revert of Make the default ctor of rtc::Thread, protected (patchset #3 id:40001 of https://codereview.webrtc.org/2981623002/ )

Reason for revert:
Break projects.

Original issue's description:
> 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

TBR=kthelgason@webrtc.org,tommi@webrtc.org
# Skipping CQ checks because original CL landed less than 1 days ago.
NOPRESUBMIT=true
NOTREECHECKS=true
NOTRY=true
BUG=none

Review-Url: https://codereview.webrtc.org/2979963002
Cr-Commit-Position: refs/heads/master@{#19003}
Committed: https://chromium.googlesource.com/external/webrtc/+/a117b04113f8e6f6684e050b8a3a54b44e74672a

[charujain, 2017-07-13 14:06:23]

The CQ bit was checked by charujain@webrtc.org

[charujain, 2017-07-13 14:06:23]

Created Revert of Make the default ctor of rtc::Thread, protected

[commit-bot: I haz the power, 2017-07-13 14:06:31]

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 14:06:39]

CQ is committing da patch.

Bot data: {"patchset_id": 1, "attempt_start_ts": 1499954783207090, "parent_rev":
"a5f1de1e6541de03f944bcbf49be87c01f57a18b", "commit_rev":
"a117b04113f8e6f6684e050b8a3a54b44e74672a"}

[commit-bot: I haz the power, 2017-07-13 14:06:44]

Description was changed from

==========
Revert of Make the default ctor of rtc::Thread, protected (patchset #3 id:40001
of https://codereview.webrtc.org/2981623002/ )

Reason for revert:
Break projects.

Original issue's description:
> 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...

TBR=kthelgason@webrtc.org,tommi@webrtc.org
# Skipping CQ checks because original CL landed less than 1 days ago.
NOPRESUBMIT=true
NOTREECHECKS=true
NOTRY=true
BUG=none
==========

to

==========
Revert of Make the default ctor of rtc::Thread, protected (patchset #3 id:40001
of https://codereview.webrtc.org/2981623002/ )

Reason for revert:
Break projects.

Original issue's description:
> 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...

TBR=kthelgason@webrtc.org,tommi@webrtc.org
# Skipping CQ checks because original CL landed less than 1 days ago.
NOPRESUBMIT=true
NOTREECHECKS=true
NOTRY=true
BUG=none

Review-Url: https://codereview.webrtc.org/2979963002
Cr-Commit-Position: refs/heads/master@{#19003}
Committed:
https://chromium.googlesource.com/external/webrtc/+/a117b04113f8e6f6684e050b8...
==========

[commit-bot: I haz the power, 2017-07-13 14:06:45]

Committed patchset #1 (id:1) as
https://chromium.googlesource.com/external/webrtc/+/a117b04113f8e6f6684e050b8...

[tommi, 2017-07-14 10:24:02]

A revert of this CL (patchset #1 id:1) has been created in
https://codereview.webrtc.org/2977953002/ by tommi@webrtc.org.

The reason for reverting is: Preparing partial re-land. Won't make the ctor
protected but will mark it as deprecated and keep all other changes..