Move in-GPU mojo:media app to new thread

Move in-GPU mojo:media app to new thread

This app was moved to the main thread of the GPU
process when I killed shell::Loader.
See https://codereview.chromium.org/1889253002.

We want this running on its own background thread
because it does slow things.

This CL adds the option for embedded mojo apps to
be run on their own thread and uses the option
for mojo:media in the GPU process.

BUG=611070
TEST=watched cat videos on youtube.com with android build, which exercises in-GPU mojo:media

Committed: https://crrev.com/017f0ef2cd86419f22f52377c161b0296f173f5b
Cr-Commit-Position: refs/heads/master@{#393852}

[Ken Rockot(use gerrit already), 2016-05-13 20:15:55]

rockot@chromium.org changed reviewers:
+ jam@chromium.org, xhwang@chromium.org

[Ken Rockot(use gerrit already), 2016-05-13 20:19:03]

PTAL

jam@ for everything
xhwang@ FYI and any review also welcome

https://codereview.chromium.org/1978843003/diff/1/content/public/common/mojo_...
File content/public/common/mojo_application_info.h (right):

https://codereview.chromium.org/1978843003/diff/1/content/public/common/mojo_...
content/public/common/mojo_application_info.h:45: bool use_own_thread = false;
Note for review: I considered changing null application_task_runner to mean "use
your own thread" and require the main thread case to pass an explicit task
runner. That would avoid the need for this flag.

I chose to use an explicit opt-in flag instead, because I didn't want it to be
so easy for embedded apps to spawn new threads without realizing it.

[Ken Rockot(use gerrit already), 2016-05-13 20:21:30]

Description was changed from

==========
Move in-GPU mojo:media app to new thread

This app was previously running on its own thread, but I
undid that when removing the shell Loader interface. Turns out
we actually want this app on its own thread when in the GPU
process.

This CL adds the option for embedded mojo apps to be run on
their own thread and uses this option for mojo:media when run
in the GPU process.

BUG=611070
==========

to

==========
Move in-GPU mojo:media app to new thread

This app was previously running on its own thread, but I
undid that when removing the shell Loader interface.
See https://codereview.chromium.org/1889253002.

As it turns out,  we actually did want this app on its own
thread when running in the GPU process.

This CL adds the option for embedded mojo apps to be run on
their own thread and uses the option for mojo:media in the
GPU process.

BUG=611070
==========

[Ken Rockot(use gerrit already), 2016-05-13 20:42:31]

Description was changed from

==========
Move in-GPU mojo:media app to new thread

This app was previously running on its own thread, but I
undid that when removing the shell Loader interface.
See https://codereview.chromium.org/1889253002.

As it turns out,  we actually did want this app on its own
thread when running in the GPU process.

This CL adds the option for embedded mojo apps to be run on
their own thread and uses the option for mojo:media in the
GPU process.

BUG=611070
==========

to

==========
Move in-GPU mojo:media app to new thread

This app was previously running on its own thread, but I
undid that when removing the shell Loader interface.
See https://codereview.chromium.org/1889253002.

As it turns out,  we actually did want this app on its own
thread when running in the GPU process.

This CL adds the option for embedded mojo apps to be run on
their own thread and uses the option for mojo:media in the
GPU process.

BUG=611070
TEST=watched cat videos on youtube with android build
==========

[Fady Samuel, 2016-05-13 20:43:14]

On 2016/05/13 20:19:03, Ken Rockot wrote:
> PTAL
> 
> jam@ for everything
> xhwang@ FYI and any review also welcome
> 
>
https://codereview.chromium.org/1978843003/diff/1/content/public/common/mojo_...
> File content/public/common/mojo_application_info.h (right):
> 
>
https://codereview.chromium.org/1978843003/diff/1/content/public/common/mojo_...
> content/public/common/mojo_application_info.h:45: bool use_own_thread = false;
> Note for review: I considered changing null application_task_runner to mean
"use
> your own thread" and require the main thread case to pass an explicit task
> runner. That would avoid the need for this flag.
> 
> I chose to use an explicit opt-in flag instead, because I didn't want it to be
> so easy for embedded apps to spawn new threads without realizing it.

Drive-by question: I haven't been following the mojo media work. Does this also
need to be componentized for mus?

[Ken Rockot(use gerrit already), 2016-05-13 21:09:14]

On 2016/05/13 at 20:43:14, fsamuel wrote:
> On 2016/05/13 20:19:03, Ken Rockot wrote:
> > PTAL
> > 
> > jam@ for everything
> > xhwang@ FYI and any review also welcome
> > 
> >
https://codereview.chromium.org/1978843003/diff/1/content/public/common/mojo_...
> > File content/public/common/mojo_application_info.h (right):
> > 
> >
https://codereview.chromium.org/1978843003/diff/1/content/public/common/mojo_...
> > content/public/common/mojo_application_info.h:45: bool use_own_thread =
false;
> > Note for review: I considered changing null application_task_runner to mean
"use
> > your own thread" and require the main thread case to pass an explicit task
> > runner. That would avoid the need for this flag.
> > 
> > I chose to use an explicit opt-in flag instead, because I didn't want it to
be
> > so easy for embedded apps to spawn new threads without realizing it.
> 
> Drive-by question: I haven't been following the mojo media work. Does this
also need to be componentized for mus?

I think this stuff will make sense to keep close to whatever process management
and application/shell embedding framework we use. Because content process
management is far more complete than mojo runner's, I don't see us using the
latter in a real production environment for a while yet.

But yeah eventually this should be componentized along with content's process
mgmt and mojo shell integration code IMHO

[Ken Rockot(use gerrit already), 2016-05-16 13:58:15]

Description was changed from

==========
Move in-GPU mojo:media app to new thread

This app was previously running on its own thread, but I
undid that when removing the shell Loader interface.
See https://codereview.chromium.org/1889253002.

As it turns out,  we actually did want this app on its own
thread when running in the GPU process.

This CL adds the option for embedded mojo apps to be run on
their own thread and uses the option for mojo:media in the
GPU process.

BUG=611070
TEST=watched cat videos on youtube with android build
==========

to

==========
Move in-GPU mojo:media app to new thread

This app was moved to the main thread of the GPU
process when I killed shell::Loader.
See https://codereview.chromium.org/1889253002.

We want this running on its own background thread
because it does slow things.

This CL adds the option for embedded mojo apps to
be run on their own thread and uses the option
for mojo:media in the GPU process.

BUG=611070
TEST=watched cat videos on youtube.com with android build, which exercises
in-GPU mojo:media
==========

[jam, 2016-05-16 15:54:23]

lgtm

[Ken Rockot(use gerrit already), 2016-05-16 15:56:21]

The CQ bit was checked by rockot@chromium.org

[commit-bot: I haz the power, 2016-05-16 15:56:34]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1978843003/20001
View timeline at
 https://chromium-cq-status.appspot.com/patch-timeline/1978843003/20001

[commit-bot: I haz the power, 2016-05-16 17:16:09]

Committed patchset #2 (id:20001)

[commit-bot: I haz the power, 2016-05-16 17:17:50]

Description was changed from

==========
Move in-GPU mojo:media app to new thread

This app was moved to the main thread of the GPU
process when I killed shell::Loader.
See https://codereview.chromium.org/1889253002.

We want this running on its own background thread
because it does slow things.

This CL adds the option for embedded mojo apps to
be run on their own thread and uses the option
for mojo:media in the GPU process.

BUG=611070
TEST=watched cat videos on youtube.com with android build, which exercises
in-GPU mojo:media
==========

to

==========
Move in-GPU mojo:media app to new thread

This app was moved to the main thread of the GPU
process when I killed shell::Loader.
See https://codereview.chromium.org/1889253002.

We want this running on its own background thread
because it does slow things.

This CL adds the option for embedded mojo apps to
be run on their own thread and uses the option
for mojo:media in the GPU process.

BUG=611070
TEST=watched cat videos on youtube.com with android build, which exercises
in-GPU mojo:media

Committed: https://crrev.com/017f0ef2cd86419f22f52377c161b0296f173f5b
Cr-Commit-Position: refs/heads/master@{#393852}
==========

[commit-bot: I haz the power, 2016-05-16 17:17:51]

Patchset 2 (id:??) landed as
https://crrev.com/017f0ef2cd86419f22f52377c161b0296f173f5b
Cr-Commit-Position: refs/heads/master@{#393852}