Refactoring of the farend buffering scheme inside the AEC

The buffering of the farend signal is refactored in this CL.

The former buffering scheme was overly complicated and
complex as.
-It buffered twice as many data points as needed.
-It used the ring_buffer C functionality directly inside the
 delay adjustment functionality which makes that
functionality very hard to read.

In order to overcome these problems this CL does
-Change the buffering to buffer only the amount of samples
 needed.
-Wrap the ring_buffer C functionality in a wrapper class
 with methods that are more descriptive in what they do
 to affect the AEC delay.

Additional notes:
-Some minor other name changes/code changes were also
 introduced.
-The ringbuffer C functionality should be removed, but now
 is not the time to do it as the rest of the code is very
 adapted to the wrapping behavior of the ringbuffer. It is
 better to simplify the surrounding code before doing that.

The changes have been tested to be bitexact.

This CL is chained to the CL https://codereview.webrtc.org/2321483002/
and will be followed by another CL.

BUG=webrtc:5298, webrtc:6018
Committed: https://crrev.com/a421ddd60eb15a19b675ceaa4e241bd15cc86f8e
Cr-Commit-Position: refs/heads/master@{#14188}

[peah-webrtc, 2016-09-08 11:41:14]

Patchset #1 (id:1) has been deleted

[peah-webrtc, 2016-09-08 11:41:23]

Patchset #1 (id:20001) has been deleted

[peah-webrtc, 2016-09-08 11:41:29]

Patchset #1 (id:40001) has been deleted

[peah-webrtc, 2016-09-08 11:41:37]

Patchset #1 (id:60001) has been deleted

[peah-webrtc, 2016-09-08 11:41:44]

Patchset #1 (id:80001) has been deleted

[peah-webrtc, 2016-09-08 12:14:15]

Description was changed from

==========
Refactoring of the farend buffering scheme inside the AEC

BUG=
==========

to

==========
The buffering of the farend signal is refactored in this CL.

The former buffering scheme was overly complicated and 
complex as.
-It buffered twice as many data points as needed.
-It used the ring_buffer C functionality directly inside the
 delay adjustment functionality which makes that
functionality very hard to read.

In order to overcome these problems this CL does
-Change the buffering to buffer only the amount of samples
 needed.
-Wrap the ring_buffer C functionality in a wrapper class
 with methods that are more descriptive in what they do
 to affect the AEC delay.

Additional notes:
-Some minor other name changes/code changes were also
 introduced.
-The ringbuffer C functionality should be removed, but now
 is not the time to do it as the rest of the code is very
 adapted to the wrapping behavior of the ringbuffer. It is
 better to simplify the surrounding code before doing that.


The changes have been tested to be bitexact. 

This CL is chained to the CL https://codereview.webrtc.org/2321483002/ 
and will be followed by another CL.

BUG=webrtc:5298, webrtc:6018
==========

[peah-webrtc, 2016-09-08 12:14:29]

peah@webrtc.org changed reviewers:
+ henrik.lundin@webrtc.org

[hlundin-webrtc, 2016-09-09 10:47:16]

Good. Just a few minor comments.

https://codereview.webrtc.org/2319693003/diff/100001/webrtc/modules/audio_pro...
File webrtc/modules/audio_processing/aec/aec_core.cc (right):

https://codereview.webrtc.org/2319693003/diff/100001/webrtc/modules/audio_pro...
webrtc/modules/audio_processing/aec/aec_core.cc:187:
FarendBlockBuffer::FarendBlockBuffer() {
What makes this specific to farend? Consider renaming to BlockBuffer.

https://codereview.webrtc.org/2319693003/diff/100001/webrtc/modules/audio_pro...
webrtc/modules/audio_processing/aec/aec_core.cc:196: void
FarendBlockBuffer::Init() {
Rename this to Reinit(). If you have to call (Re)Init() on a newly constructed
FarendBlockBuffer, please, do so in the ctor.

https://codereview.webrtc.org/2319693003/diff/100001/webrtc/modules/audio_pro...
webrtc/modules/audio_processing/aec/aec_core.cc:228: int
FarendBlockBuffer::Size() {
size_t

https://codereview.webrtc.org/2319693003/diff/100001/webrtc/modules/audio_pro...
webrtc/modules/audio_processing/aec/aec_core.cc:232: int
FarendBlockBuffer::AvaliableSpace() {
size_t

[peah-webrtc, 2016-09-12 08:10:22]

https://codereview.webrtc.org/2319693003/diff/100001/webrtc/modules/audio_pro...
File webrtc/modules/audio_processing/aec/aec_core.cc (right):

https://codereview.webrtc.org/2319693003/diff/100001/webrtc/modules/audio_pro...
webrtc/modules/audio_processing/aec/aec_core.cc:187:
FarendBlockBuffer::FarendBlockBuffer() {
On 2016/09/09 10:47:15, hlundin-webrtc wrote:
> What makes this specific to farend? Consider renaming to BlockBuffer.

Great point!
Done.

https://codereview.webrtc.org/2319693003/diff/100001/webrtc/modules/audio_pro...
webrtc/modules/audio_processing/aec/aec_core.cc:196: void
FarendBlockBuffer::Init() {
On 2016/09/09 10:47:15, hlundin-webrtc wrote:
> Rename this to Reinit(). If you have to call (Re)Init() on a newly constructed
> FarendBlockBuffer, please, do so in the ctor.

Done.

https://codereview.webrtc.org/2319693003/diff/100001/webrtc/modules/audio_pro...
webrtc/modules/audio_processing/aec/aec_core.cc:228: int
FarendBlockBuffer::Size() {
On 2016/09/09 10:47:15, hlundin-webrtc wrote:
> size_t

Done.

https://codereview.webrtc.org/2319693003/diff/100001/webrtc/modules/audio_pro...
webrtc/modules/audio_processing/aec/aec_core.cc:232: int
FarendBlockBuffer::AvaliableSpace() {
On 2016/09/09 10:47:15, hlundin-webrtc wrote:
> size_t

Done.

[hlundin-webrtc, 2016-09-12 08:15:04]

lgtm

[peah-webrtc, 2016-09-12 14:00:30]

The CQ bit was checked by peah@webrtc.org

[peah-webrtc, 2016-09-12 14:00:30]

The patchset sent to the CQ was uploaded after l-g-t-m from
henrik.lundin@webrtc.org
Link to the patchset: https://codereview.webrtc.org/2319693003/#ps140001 (title:
"Rebase")

[commit-bot: I haz the power, 2016-09-12 14:00:40]

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, 2016-09-12 16:01:13]

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

[commit-bot: I haz the power, 2016-09-12 16:01:15]

Try jobs failed on following builders:
  android_dbg on master.tryserver.webrtc (JOB_TIMED_OUT, no build URL)

[peah-webrtc, 2016-09-12 18:18:51]

The CQ bit was checked by peah@webrtc.org

[commit-bot: I haz the power, 2016-09-12 18:19:00]

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, 2016-09-12 18:27:16]

Description was changed from

==========
The buffering of the farend signal is refactored in this CL.

The former buffering scheme was overly complicated and 
complex as.
-It buffered twice as many data points as needed.
-It used the ring_buffer C functionality directly inside the
 delay adjustment functionality which makes that
functionality very hard to read.

In order to overcome these problems this CL does
-Change the buffering to buffer only the amount of samples
 needed.
-Wrap the ring_buffer C functionality in a wrapper class
 with methods that are more descriptive in what they do
 to affect the AEC delay.

Additional notes:
-Some minor other name changes/code changes were also
 introduced.
-The ringbuffer C functionality should be removed, but now
 is not the time to do it as the rest of the code is very
 adapted to the wrapping behavior of the ringbuffer. It is
 better to simplify the surrounding code before doing that.


The changes have been tested to be bitexact. 

This CL is chained to the CL https://codereview.webrtc.org/2321483002/ 
and will be followed by another CL.

BUG=webrtc:5298, webrtc:6018
==========

to

==========
The buffering of the farend signal is refactored in this CL.

The former buffering scheme was overly complicated and 
complex as.
-It buffered twice as many data points as needed.
-It used the ring_buffer C functionality directly inside the
 delay adjustment functionality which makes that
functionality very hard to read.

In order to overcome these problems this CL does
-Change the buffering to buffer only the amount of samples
 needed.
-Wrap the ring_buffer C functionality in a wrapper class
 with methods that are more descriptive in what they do
 to affect the AEC delay.

Additional notes:
-Some minor other name changes/code changes were also
 introduced.
-The ringbuffer C functionality should be removed, but now
 is not the time to do it as the rest of the code is very
 adapted to the wrapping behavior of the ringbuffer. It is
 better to simplify the surrounding code before doing that.


The changes have been tested to be bitexact. 

This CL is chained to the CL https://codereview.webrtc.org/2321483002/ 
and will be followed by another CL.

BUG=webrtc:5298, webrtc:6018
==========

[commit-bot: I haz the power, 2016-09-12 18:27:17]

Committed patchset #3 (id:140001)

[commit-bot: I haz the power, 2016-09-12 18:27:29]

Description was changed from

==========
The buffering of the farend signal is refactored in this CL.

The former buffering scheme was overly complicated and 
complex as.
-It buffered twice as many data points as needed.
-It used the ring_buffer C functionality directly inside the
 delay adjustment functionality which makes that
functionality very hard to read.

In order to overcome these problems this CL does
-Change the buffering to buffer only the amount of samples
 needed.
-Wrap the ring_buffer C functionality in a wrapper class
 with methods that are more descriptive in what they do
 to affect the AEC delay.

Additional notes:
-Some minor other name changes/code changes were also
 introduced.
-The ringbuffer C functionality should be removed, but now
 is not the time to do it as the rest of the code is very
 adapted to the wrapping behavior of the ringbuffer. It is
 better to simplify the surrounding code before doing that.


The changes have been tested to be bitexact. 

This CL is chained to the CL https://codereview.webrtc.org/2321483002/ 
and will be followed by another CL.

BUG=webrtc:5298, webrtc:6018
==========

to

==========
The buffering of the farend signal is refactored in this CL.

The former buffering scheme was overly complicated and
complex as.
-It buffered twice as many data points as needed.
-It used the ring_buffer C functionality directly inside the
 delay adjustment functionality which makes that
functionality very hard to read.

In order to overcome these problems this CL does
-Change the buffering to buffer only the amount of samples
 needed.
-Wrap the ring_buffer C functionality in a wrapper class
 with methods that are more descriptive in what they do
 to affect the AEC delay.

Additional notes:
-Some minor other name changes/code changes were also
 introduced.
-The ringbuffer C functionality should be removed, but now
 is not the time to do it as the rest of the code is very
 adapted to the wrapping behavior of the ringbuffer. It is
 better to simplify the surrounding code before doing that.

The changes have been tested to be bitexact.

This CL is chained to the CL https://codereview.webrtc.org/2321483002/
and will be followed by another CL.

BUG=webrtc:5298, webrtc:6018

Committed: https://crrev.com/a421ddd60eb15a19b675ceaa4e241bd15cc86f8e
Cr-Commit-Position: refs/heads/master@{#14188}
==========

[commit-bot: I haz the power, 2016-09-12 18:27:30]

Patchset 3 (id:??) landed as
https://crrev.com/a421ddd60eb15a19b675ceaa4e241bd15cc86f8e
Cr-Commit-Position: refs/heads/master@{#14188}