MSE: Start removing Blink-side support for LegacyFrameProcessor

MSE: Start removing Blink-side support for LegacyFrameProcessor

This is the first of a three-sided change to remove LegacyFrameProcessor
from Blink and Chromium now that the new FrameProcessor is stabilized.
Once Chromium no longer implements the FrameProcessorChoice version of
WMSI::addSourceBuffer(), a third change will remove the default Blink
implemenetations of addSourceBuffer() and the FrameProcessorChoice enum.

R=acolwell@chromium.org,abarth@chromium.org
BUG=249422
TEST=No MSE layout test regression locally on Linux

Committed: https://src.chromium.org/viewvc/blink?view=rev&revision=176379

[wolenetz, 2014-06-03 02:54:15]

In anticipation of hopefully removing LegacyFrameProcessor soon:
PTAL @ PS1:
acolwell@: everything
abarth@: public/platform

This is part 1/3.
Part 2 (for after this lands and is rolled into Chromium) contains the bulk of
the actual removal: https://codereview.chromium.org/315483002/
Part 3 completes the removal: https://codereview.chromium.org/309933002/

This 3-sided change depends on https://codereview.chromium.org/307263003/
landing first and baking in Canary for a short while.

I would have chosen a Chromium->Blink->Chromium CL sequence for this 3-sided
change, but the |enum FrameProcessorChoice| definition is in Blink and would
still be needed after the first Chromium patch, and be obsolete later,
necessitating CL#4 to remove it.

The default implementation for WebMediaSource::addSourceBuffer([with
FrameProcessorChoice]) introduced in this CL is necessary so WebMediaSourceImpl
can still be a concrete class after the removal of the Chromium side
implementation of that virtual method signature. The default implementations are
removed in part 3.

[wolenetz, 2014-06-09 20:33:41]

PTAL @ PS2 (just a rebase). Intent is to land this by EOW or early next week if
still no regressions seen with new FrameProcessor.

[acolwell GONE FROM CHROMIUM, 2014-06-13 18:30:40]

lgtm

https://codereview.chromium.org/310733002/diff/20001/public/platform/WebMedia...
File public/platform/WebMediaSource.h (right):

https://codereview.chromium.org/310733002/diff/20001/public/platform/WebMedia...
public/platform/WebMediaSource.h:61: 
nit: Remove unnecessary whitespace on this line?

https://codereview.chromium.org/310733002/diff/20001/public/platform/WebMedia...
public/platform/WebMediaSource.h:69: return addSourceBuffer(type, codecs,
webSourceBuffer);
I'm assuming you are doing this so you don't have to wait for a DEPS roll to
land https://codereview.chromium.org/315483002/ right?

[wolenetz, 2014-06-16 20:00:24]

acolwell@: Thanks for review. PTAL @ my response to your question regarding DEPS
roll.

abarth@: please review public/platform

https://codereview.chromium.org/310733002/diff/20001/public/platform/WebMedia...
File public/platform/WebMediaSource.h (right):

https://codereview.chromium.org/310733002/diff/20001/public/platform/WebMedia...
public/platform/WebMediaSource.h:61: 
On 2014/06/13 18:30:40, acolwell wrote:
> nit: Remove unnecessary whitespace on this line?

Done.

https://codereview.chromium.org/310733002/diff/20001/public/platform/WebMedia...
public/platform/WebMediaSource.h:69: return addSourceBuffer(type, codecs,
webSourceBuffer);
On 2014/06/13 18:30:40, acolwell wrote:
> I'm assuming you are doing this so you don't have to wait for a DEPS roll to
> land https://codereview.chromium.org/315483002/ right?

That Chromium CL still needs this to land first and be rolled in Blink DEPS.
Otherwise, I would need both implementations added in the first Chromium CL and
a later Chromium cleanup CL. Overall, I chose the sequence of
Blink->roll->Chromium->Blink CLs because the FrameProcessorChoice enum is
defined in Blink and will be needed until Chromium no longer uses it. Once the
Chromium CL is landed, this default implementation of the soon-to-be obsolete
method signature will be required to be able to construct a concrete Chromium
WMSI.

Did I miss a better way of doing this or misunderstand your question?

[wolenetz, 2014-06-16 20:14:25]

On 2014/06/16 20:00:24, wolenetz wrote:
> acolwell@: Thanks for review. PTAL @ my response to your question regarding
DEPS
> roll.
> 
> abarth@: please review public/platform
> 
>
https://codereview.chromium.org/310733002/diff/20001/public/platform/WebMedia...
> File public/platform/WebMediaSource.h (right):
> 
>
https://codereview.chromium.org/310733002/diff/20001/public/platform/WebMedia...
> public/platform/WebMediaSource.h:61: 
> On 2014/06/13 18:30:40, acolwell wrote:
> > nit: Remove unnecessary whitespace on this line?
> 
> Done.
> 
>
https://codereview.chromium.org/310733002/diff/20001/public/platform/WebMedia...
> public/platform/WebMediaSource.h:69: return addSourceBuffer(type, codecs,
> webSourceBuffer);
> On 2014/06/13 18:30:40, acolwell wrote:
> > I'm assuming you are doing this so you don't have to wait for a DEPS roll to
> > land https://codereview.chromium.org/315483002/ right?
> 
> That Chromium CL still needs this to land first and be rolled in Blink DEPS.
> Otherwise, I would need both implementations added in the first Chromium CL
and
> a later Chromium cleanup CL. Overall, I chose the sequence of
> Blink->roll->Chromium->Blink CLs because the FrameProcessorChoice enum is
> defined in Blink and will be needed until Chromium no longer uses it. Once the
> Chromium CL is landed, this default implementation of the soon-to-be obsolete
> method signature will be required to be able to construct a concrete Chromium
> WMSI.
> 
> Did I miss a better way of doing this or misunderstand your question?

I chatted with acolwell@ offline. I'll have a new patch set shortly that
contains a trivial no-op default implementation of the old addSourceBuffer
signature (since that default implementation should never be actually run
because this PS has Blink calling the new one in default impl, which calls the
for-realz old one in Chromium; and once DEPS rolls and Chromium CL lands,
neither of the default impl for addSourceBuffer() will be run.

[wolenetz, 2014-06-16 20:49:06]

abarth@: PTAL @ PS4. Thank you.

[wolenetz, 2014-06-17 17:40:49]

On 2014/06/16 20:49:06, wolenetz wrote:
> abarth@: PTAL @ PS4. Thank you.

abarth@: ping. Thank you.

[abarth-chromium, 2014-06-17 21:49:11]

lgtm

[abarth-chromium, 2014-06-17 21:49:20]

Sorry for the delay.

[wolenetz, 2014-06-18 01:19:51]

Thank you for reviews.

[wolenetz, 2014-06-18 01:19:56]

The CQ bit was checked by wolenetz@chromium.org

[commit-bot: I haz the power, 2014-06-18 01:20:39]

CQ is trying da patch. Follow status at
 https://chromium-status.appspot.com/cq/wolenetz@chromium.org/310733002/60001

[commit-bot: I haz the power, 2014-06-18 02:57:17]

Change committed as 176379