AudioCodingModuleImpl::Encode: Use a Buffer instead of a stack-allocated array

AudioCodingModuleImpl::Encode: Use a Buffer instead of a stack-allocated array

The Buffer is saved between calls, so after the initial allocation
it'll already be allocated and of the right size. The stack-allocated
array had the advantage of requiring no heap allocation at all, but
for most popular encoders it ended up allocating about 15 kB too much,
and now that we allow user-defined encoders there was also the
(remote) possibility that the buffer would actually be too small.

R=henrik.lundin@webrtc.org

Committed: https://chromium.googlesource.com/external/webrtc/+/0163fb2ad7c95a0ac20a8a9861073e2a16fa77b4

[kwiberg-webrtc, 2015-08-25 10:26:58]

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

[hlundin-webrtc, 2015-08-25 12:43:43]

One comment.

https://codereview.webrtc.org/1303413003/diff/1/webrtc/modules/audio_coding/m...
File webrtc/modules/audio_coding/main/acm2/audio_coding_module_impl.cc (right):

https://codereview.webrtc.org/1303413003/diff/1/webrtc/modules/audio_coding/m...
webrtc/modules/audio_coding/main/acm2/audio_coding_module_impl.cc:187: if
(encode_buffer_.size() == 0 && !encoded_info.send_even_if_empty) {
Why change this while still using encoded_info.encoded_bytes below? They hold
the same information, but I think it is cleaner if we stick to reading one of
them.

[kwiberg-webrtc, 2015-08-25 13:20:24]

https://codereview.webrtc.org/1303413003/diff/1/webrtc/modules/audio_coding/m...
File webrtc/modules/audio_coding/main/acm2/audio_coding_module_impl.cc (right):

https://codereview.webrtc.org/1303413003/diff/1/webrtc/modules/audio_coding/m...
webrtc/modules/audio_coding/main/acm2/audio_coding_module_impl.cc:187: if
(encode_buffer_.size() == 0 && !encoded_info.send_even_if_empty) {
On 2015/08/25 12:43:43, hlundin-webrtc wrote:
> Why change this while still using encoded_info.encoded_bytes below? They hold
> the same information, but I think it is cleaner if we stick to reading one of
> them.

Indeed, that was dismeticulous of me. Fixed (by using encode_buffer_.size()
everywhere).

[hlundin-webrtc, 2015-08-26 13:10:17]

lgtm

https://codereview.webrtc.org/1303413003/diff/1/webrtc/modules/audio_coding/m...
File webrtc/modules/audio_coding/main/acm2/audio_coding_module_impl.cc (right):

https://codereview.webrtc.org/1303413003/diff/1/webrtc/modules/audio_coding/m...
webrtc/modules/audio_coding/main/acm2/audio_coding_module_impl.cc:187: if
(encode_buffer_.size() == 0 && !encoded_info.send_even_if_empty) {
On 2015/08/25 13:20:24, kwiberg-webrtc wrote:
> On 2015/08/25 12:43:43, hlundin-webrtc wrote:
> > Why change this while still using encoded_info.encoded_bytes below? They
hold
> > the same information, but I think it is cleaner if we stick to reading one
of
> > them.
> 
> Indeed, that was dismeticulous of me. Fixed (by using encode_buffer_.size()
> everywhere).

Meticulosity is restored.

[kwiberg-webrtc, 2015-08-26 13:36:19]

The CQ bit was checked by kwiberg@webrtc.org

[commit-bot: I haz the power, 2015-08-26 13:36:24]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1303413003/20001
View timeline at
 https://chromium-cq-status.appspot.com/patch-timeline/1303413003/20001

[commit-bot: I haz the power, 2015-08-26 15:36:35]

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

[commit-bot: I haz the power, 2015-08-26 15:36:36]

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

[kwiberg-webrtc, 2015-08-26 18:24:42]

Committed patchset #2 (id:20001) manually as
0163fb2ad7c95a0ac20a8a9861073e2a16fa77b4 (presubmit successful).