Move copyonwritebuffer to rtc_base_approved.

Move copyonwritebuffer to rtc_base_approved.
The other buffer classes as well as all other dependencies are in rtc_base_approved, so I think this is a better place for it.  Additionally I found that code in Chromium that already depends on the other buffer classes but now depends on the CopyOnWriteBuffer class, needed to have their build files updated and they previously depended on the buffer classes in rtc_base_approved.

TBR=jbauch@webrtc.org

Committed: https://crrev.com/ebfbab50596e3861f936654e7f46385939084266
Cr-Commit-Position: refs/heads/master@{#12059}

[tommi, 2016-03-19 17:36:48]

The CQ bit was checked by tommi@webrtc.org

[commit-bot: I haz the power, 2016-03-19 17:36:54]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1820643002/1
View timeline at
 https://chromium-cq-status.appspot.com/patch-timeline/1820643002/1

[joachim, 2016-03-19 17:43:12]

lgtm

[commit-bot: I haz the power, 2016-03-19 18:36:24]

Committed patchset #1 (id:1)

[commit-bot: I haz the power, 2016-03-19 18:36:27]

Description was changed from

==========
Move copyonwritebuffer to rtc_base_approved.
The other buffer classes as well as all other dependencies are in
rtc_base_approved, so I think this is a better place for it.  Additionally I
found that code in Chromium that already depends on the other buffer classes but
now depends on the CopyOnWriteBuffer class, needed to have their build files
updated and they previously depended on the buffer classes in rtc_base_approved.

TBR=jbauch@webrtc.org
==========

to

==========
Move copyonwritebuffer to rtc_base_approved.
The other buffer classes as well as all other dependencies are in
rtc_base_approved, so I think this is a better place for it.  Additionally I
found that code in Chromium that already depends on the other buffer classes but
now depends on the CopyOnWriteBuffer class, needed to have their build files
updated and they previously depended on the buffer classes in rtc_base_approved.

TBR=jbauch@webrtc.org

Committed: https://crrev.com/ebfbab50596e3861f936654e7f46385939084266
Cr-Commit-Position: refs/heads/master@{#12059}
==========

[commit-bot: I haz the power, 2016-03-19 18:36:28]

Patchset 1 (id:??) landed as
https://crrev.com/ebfbab50596e3861f936654e7f46385939084266
Cr-Commit-Position: refs/heads/master@{#12059}