Remove unused variables.

Remove unused variables.

These variables trigger compiler warnings (and thus build errors) when
DISALLOW_COPY_AND_ASSIGN is changed to use "= delete", and thus must be removed
before that lands.

https://codereview.chromium.org/1701063003 (a while ago) added the variable in
chrome/browser/chromeos/arc/arc_service_launcher.h, which was never used.

https://codereview.chromium.org/1866043006 removed the uses of the variables in
cc/tiles/tile_manager.cc, but not the variables themselves.

https://codereview.chromium.org/1899363002 added all the media/ plumbing in
order to set MojoVideoDecoder::gpu_factories_, which is unused.

https://codereview.chromium.org/1961573002 added the variable in
net/spdy/spdy_framer_test.cc, which is unused.

BUG=447156
TEST=none
CQ_INCLUDE_TRYBOTS=tryserver.blink:linux_blink_rel

Committed: https://crrev.com/92b8e44c524807b245461461925bbb928af21b38
Cr-Commit-Position: refs/heads/master@{#396289}

[Peter Kasting, 2016-05-26 06:44:37]

pkasting@chromium.org changed reviewers:
+ arthurhsu@chromium.org, dahollings@chromium.org, sandersd@chromium.org

[Peter Kasting, 2016-05-26 06:44:37]

arthurhsu: 	chrome/browser/chromeos/arc/arc_service_launcher.h
sandersd: media/
dahollings: net/spdy/spdy_framer_test.cc

[Luis Héctor Chávez, 2016-05-26 15:25:11]

lhchavez@chromium.org changed reviewers:
+ lhchavez@chromium.org

[Luis Héctor Chávez, 2016-05-26 15:25:11]

chrome/browser/chromeos/arc/* LGTM

[arthurhsu, 2016-05-26 16:39:05]

On 2016/05/26 06:44:37, Peter Kasting wrote:
> arthurhsu: 	chrome/browser/chromeos/arc/arc_service_launcher.h

LGTM

[sandersd (OOO until July 31), 2016-05-26 18:04:38]

It was no accident that |gpu_factories_| was plumbed through to
MojoVideoDecoder. Is there a simple way to mark it as used and avoid having to
re-do all the plumbing work in the next CL?

[Peter Kasting, 2016-05-26 18:10:01]

On 2016/05/26 18:04:38, sandersd wrote:
> It was no accident that |gpu_factories_| was plumbed through to
> MojoVideoDecoder. Is there a simple way to mark it as used and avoid having to
> re-do all the plumbing work in the next CL?

How soon are you landing that CL?

Note that as soon as I land the "= delete" change, you won't be able to land a
patch that plumbs through a variable but doesn't use it.  Generally people are
encouraged to plumb this sort of thing through in the CL that adds the initial
use of the variable.

[dahollings, 2016-05-26 18:13:13]

Description was changed from

==========
Remove unused variables.

These variables trigger compiler warnings (and thus build errors) when
DISALLOW_COPY_AND_ASSIGN is changed to use "= delete", and thus must be removed
before that lands.

https://codereview.chromium.org/1701063003 (a while ago) added the variable in
chrome/browser/chromeos/arc/arc_service_launcher.h, which was never used.

https://codereview.chromium.org/1899363002 added all the media/ plumbing in
order to set MojoVideoDecoder::gpu_factories_, which is unused.

https://codereview.chromium.org/1961573002 added the variable in
net/spdy/spdy_framer_test.cc, which is unused.

BUG=447156
TEST=none
==========

to

==========
Remove unused variables.

These variables trigger compiler warnings (and thus build errors) when
DISALLOW_COPY_AND_ASSIGN is changed to use "= delete", and thus must be removed
before that lands.

https://codereview.chromium.org/1701063003 (a while ago) added the variable in
chrome/browser/chromeos/arc/arc_service_launcher.h, which was never used.

https://codereview.chromium.org/1899363002 added all the media/ plumbing in
order to set MojoVideoDecoder::gpu_factories_, which is unused.

https://codereview.chromium.org/1961573002 added the variable in
net/spdy/spdy_framer_test.cc, which is unused.

BUG=447156
TEST=none
==========

[dahollings, 2016-05-26 18:13:13]

dahollings@chromium.org changed reviewers:
+ bnc@chromium.org
- dahollings@chromium.org

[sandersd (OOO until July 31), 2016-05-26 18:18:57]

On 2016/05/26 18:10:01, Peter Kasting wrote:
> On 2016/05/26 18:04:38, sandersd wrote:
> > It was no accident that |gpu_factories_| was plumbed through to
> > MojoVideoDecoder. Is there a simple way to mark it as used and avoid having
to
> > re-do all the plumbing work in the next CL?
> 
> How soon are you landing that CL?

It's likely to be a week or more.

> Note that as soon as I land the "= delete" change, you won't be able to land a
> patch that plumbs through a variable but doesn't use it.  Generally people are
> encouraged to plumb this sort of thing through in the CL that adds the initial
> use of the variable.

I hate to complain here, since I like the theory of your change, but that policy
encourages excessively large, feature-complete CLs. There must be an escape
hatch for those of us that want to break up large changes into smaller, more
reviewable pieces.

This specific case isn't so bad (23 lines), so this CL lgtm, but I was still
hoping for an official answer on avoiding this compiler warning in an explicit
way.

[Bence, 2016-05-26 18:35:27]

net/spdy LGTM

[Peter Kasting, 2016-05-26 18:37:31]

On 2016/05/26 18:18:57, sandersd wrote:
> On 2016/05/26 18:10:01, Peter Kasting wrote:
> > Note that as soon as I land the "= delete" change, you won't be able to land
a
> > patch that plumbs through a variable but doesn't use it.  Generally people
are
> > encouraged to plumb this sort of thing through in the CL that adds the
initial
> > use of the variable.
> 
> I hate to complain here, since I like the theory of your change, but that
policy
> encourages excessively large, feature-complete CLs. There must be an escape
> hatch for those of us that want to break up large changes into smaller, more
> reviewable pieces.
> 
> This specific case isn't so bad (23 lines), so this CL lgtm, but I was still
> hoping for an official answer on avoiding this compiler warning in an explicit
> way.

I can't think of a case I've encountered where the plumbing for a variable was
so complicated that it really needed to be separated from the CL that added the
initial bits of using it.  Sometimes _those_ CLs are very complicated, but the
presence of absence of this plumbing isn't usually the determining factor -- as
you note, in this case, it's less than two dozen lines, and this is a more
complicated case than most.

If you have to explicitly mark a variable as used, you should be able to do it
by either using the ignore_unused() function, or by adding a statement like
"(void)var;".  But normally this ought not to be necessary (and it introduces
the danger of such statements being left in if later CLs never get landed).

I've changed over to this mechanism and am testing to see if this really does
avoid the compiler warning.

[Peter Kasting, 2016-05-26 18:59:58]

Description was changed from

==========
Remove unused variables.

These variables trigger compiler warnings (and thus build errors) when
DISALLOW_COPY_AND_ASSIGN is changed to use "= delete", and thus must be removed
before that lands.

https://codereview.chromium.org/1701063003 (a while ago) added the variable in
chrome/browser/chromeos/arc/arc_service_launcher.h, which was never used.

https://codereview.chromium.org/1899363002 added all the media/ plumbing in
order to set MojoVideoDecoder::gpu_factories_, which is unused.

https://codereview.chromium.org/1961573002 added the variable in
net/spdy/spdy_framer_test.cc, which is unused.

BUG=447156
TEST=none
==========

to

==========
Remove unused variables.

These variables trigger compiler warnings (and thus build errors) when
DISALLOW_COPY_AND_ASSIGN is changed to use "= delete", and thus must be removed
before that lands.

https://codereview.chromium.org/1701063003 (a while ago) added the variable in
chrome/browser/chromeos/arc/arc_service_launcher.h, which was never used.

https://codereview.chromium.org/1899363002 added all the media/ plumbing in
order to set MojoVideoDecoder::gpu_factories_, which is unused.

https://codereview.chromium.org/1961573002 added the variable in
net/spdy/spdy_framer_test.cc, which is unused.

BUG=447156
TEST=none
CQ_INCLUDE_TRYBOTS=tryserver.blink:linux_blink_rel
==========

[Peter Kasting, 2016-05-26 19:02:02]

Description was changed from

==========
Remove unused variables.

These variables trigger compiler warnings (and thus build errors) when
DISALLOW_COPY_AND_ASSIGN is changed to use "= delete", and thus must be removed
before that lands.

https://codereview.chromium.org/1701063003 (a while ago) added the variable in
chrome/browser/chromeos/arc/arc_service_launcher.h, which was never used.

https://codereview.chromium.org/1899363002 added all the media/ plumbing in
order to set MojoVideoDecoder::gpu_factories_, which is unused.

https://codereview.chromium.org/1961573002 added the variable in
net/spdy/spdy_framer_test.cc, which is unused.

BUG=447156
TEST=none
CQ_INCLUDE_TRYBOTS=tryserver.blink:linux_blink_rel
==========

to

==========
Remove unused variables.

These variables trigger compiler warnings (and thus build errors) when
DISALLOW_COPY_AND_ASSIGN is changed to use "= delete", and thus must be removed
before that lands.

https://codereview.chromium.org/1701063003 (a while ago) added the variable in
chrome/browser/chromeos/arc/arc_service_launcher.h, which was never used.

https://codereview.chromium.org/1866043006 removed the uses of the variables in
cc/tiles/tile_manager.cc, but not the variables themselves.

https://codereview.chromium.org/1899363002 added all the media/ plumbing in
order to set MojoVideoDecoder::gpu_factories_, which is unused.

https://codereview.chromium.org/1961573002 added the variable in
net/spdy/spdy_framer_test.cc, which is unused.

BUG=447156
TEST=none
CQ_INCLUDE_TRYBOTS=tryserver.blink:linux_blink_rel
==========

[Peter Kasting, 2016-05-26 19:02:02]

pkasting@chromium.org changed reviewers:
+ ericrk@chromium.org

[Peter Kasting, 2016-05-26 19:02:45]

+ericrk for cc/tiles/tile_manager.cc since he reviewed
https://codereview.chromium.org/1866043006 that led to these orphaned variables.

[ericrk, 2016-05-26 19:06:54]

lgtm

Good catch, thanks.

[Peter Kasting, 2016-05-26 20:05:32]

The CQ bit was checked by pkasting@chromium.org

[Peter Kasting, 2016-05-26 20:05:33]

The patchset sent to the CQ was uploaded after l-g-t-m from
arthurhsu@chromium.org, lhchavez@chromium.org, sandersd@chromium.org,
bnc@chromium.org
Link to the patchset: https://codereview.chromium.org/2018453002/#ps40001
(title: "Remove more vars")

[commit-bot: I haz the power, 2016-05-26 20:06:15]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/2018453002/40001
View timeline at
 https://chromium-cq-status.appspot.com/patch-timeline/2018453002/40001

[commit-bot: I haz the power, 2016-05-26 21:36:17]

Description was changed from

==========
Remove unused variables.

These variables trigger compiler warnings (and thus build errors) when
DISALLOW_COPY_AND_ASSIGN is changed to use "= delete", and thus must be removed
before that lands.

https://codereview.chromium.org/1701063003 (a while ago) added the variable in
chrome/browser/chromeos/arc/arc_service_launcher.h, which was never used.

https://codereview.chromium.org/1866043006 removed the uses of the variables in
cc/tiles/tile_manager.cc, but not the variables themselves.

https://codereview.chromium.org/1899363002 added all the media/ plumbing in
order to set MojoVideoDecoder::gpu_factories_, which is unused.

https://codereview.chromium.org/1961573002 added the variable in
net/spdy/spdy_framer_test.cc, which is unused.

BUG=447156
TEST=none
CQ_INCLUDE_TRYBOTS=tryserver.blink:linux_blink_rel
==========

to

==========
Remove unused variables.

These variables trigger compiler warnings (and thus build errors) when
DISALLOW_COPY_AND_ASSIGN is changed to use "= delete", and thus must be removed
before that lands.

https://codereview.chromium.org/1701063003 (a while ago) added the variable in
chrome/browser/chromeos/arc/arc_service_launcher.h, which was never used.

https://codereview.chromium.org/1866043006 removed the uses of the variables in
cc/tiles/tile_manager.cc, but not the variables themselves.

https://codereview.chromium.org/1899363002 added all the media/ plumbing in
order to set MojoVideoDecoder::gpu_factories_, which is unused.

https://codereview.chromium.org/1961573002 added the variable in
net/spdy/spdy_framer_test.cc, which is unused.

BUG=447156
TEST=none
CQ_INCLUDE_TRYBOTS=tryserver.blink:linux_blink_rel
==========

[commit-bot: I haz the power, 2016-05-26 21:36:19]

Committed patchset #3 (id:40001)

[commit-bot: I haz the power, 2016-05-26 21:38:22]

Description was changed from

==========
Remove unused variables.

These variables trigger compiler warnings (and thus build errors) when
DISALLOW_COPY_AND_ASSIGN is changed to use "= delete", and thus must be removed
before that lands.

https://codereview.chromium.org/1701063003 (a while ago) added the variable in
chrome/browser/chromeos/arc/arc_service_launcher.h, which was never used.

https://codereview.chromium.org/1866043006 removed the uses of the variables in
cc/tiles/tile_manager.cc, but not the variables themselves.

https://codereview.chromium.org/1899363002 added all the media/ plumbing in
order to set MojoVideoDecoder::gpu_factories_, which is unused.

https://codereview.chromium.org/1961573002 added the variable in
net/spdy/spdy_framer_test.cc, which is unused.

BUG=447156
TEST=none
CQ_INCLUDE_TRYBOTS=tryserver.blink:linux_blink_rel
==========

to

==========
Remove unused variables.

These variables trigger compiler warnings (and thus build errors) when
DISALLOW_COPY_AND_ASSIGN is changed to use "= delete", and thus must be removed
before that lands.

https://codereview.chromium.org/1701063003 (a while ago) added the variable in
chrome/browser/chromeos/arc/arc_service_launcher.h, which was never used.

https://codereview.chromium.org/1866043006 removed the uses of the variables in
cc/tiles/tile_manager.cc, but not the variables themselves.

https://codereview.chromium.org/1899363002 added all the media/ plumbing in
order to set MojoVideoDecoder::gpu_factories_, which is unused.

https://codereview.chromium.org/1961573002 added the variable in
net/spdy/spdy_framer_test.cc, which is unused.

BUG=447156
TEST=none
CQ_INCLUDE_TRYBOTS=tryserver.blink:linux_blink_rel

Committed: https://crrev.com/92b8e44c524807b245461461925bbb928af21b38
Cr-Commit-Position: refs/heads/master@{#396289}
==========

[commit-bot: I haz the power, 2016-05-26 21:38:23]

Patchset 3 (id:??) landed as
https://crrev.com/92b8e44c524807b245461461925bbb928af21b38
Cr-Commit-Position: refs/heads/master@{#396289}