Get rid of the huge delay in background resize during rotation

Get rid of the huge delay in background resize during rotation

The delay to start updating the wallpaper after rotating the screen used
to be 2 seconds which was also accompanied by unnecessary clearing of
the wallpaper cache resulting in an ugly visual effect.

Now we reduced the delay to only 100 ms and we only clear the cache when
we add another display.

BUG=359654
TEST=manual

Committed: https://crrev.com/7a1ba5ffc2e68bafbeefc80a76b71f6221601712
Cr-Commit-Position: refs/heads/master@{#329507}

[afakhry, 2015-05-11 23:41:03]

afakhry@chromium.org changed reviewers:
+ bshe@chromium.org, tdanderson@chromium.org

[afakhry, 2015-05-11 23:41:04]

Hi bshe@, Could you please review this CL?

[afakhry, 2015-05-11 23:41:40]

On 2015/05/11 23:41:04, afakhry wrote:
> Hi bshe@, Could you please review this CL?

tdanderson@, could you please verify that this is visually acceptable?

[bshe, 2015-05-12 13:19:32]

On 2015/05/11 23:41:40, afakhry wrote:
> On 2015/05/11 23:41:04, afakhry wrote:
> > Hi bshe@, Could you please review this CL?
> 
> tdanderson@, could you please verify that this is visually acceptable?

Sorry, just remember something as I look at your CL. It would also worth
checking the resolution of wallpaper
after rotation. Is it at the same quality or is it worse? The cache might be a
small resolution wallpaper
which then scaled to fit the height of the rotated screen. If we clear cache, we
will load a large resolution
wallpaper so the quality of wallpaper might be better. It may not make much
difference but worth checking.

[tdanderson, 2015-05-12 14:54:12]

Strange, I'm not actually seeing the issue reproduce on ToT without your CL. Do
you see the issue reproduce, and if so, what steps are you using?

[afakhry, 2015-05-12 16:50:01]

On 2015/05/12 14:54:12, tdanderson wrote:
> Strange, I'm not actually seeing the issue reproduce on ToT without your CL.
Do
> you see the issue reproduce, and if so, what steps are you using?

@tdanderson: Just rotate the screen and wait 2 seconds.

[afakhry, 2015-05-12 16:51:32]

On 2015/05/12 13:19:32, bshe wrote:
> On 2015/05/11 23:41:40, afakhry wrote:
> > On 2015/05/11 23:41:04, afakhry wrote:
> > > Hi bshe@, Could you please review this CL?
> > 
> > tdanderson@, could you please verify that this is visually acceptable?
> 
> Sorry, just remember something as I look at your CL. It would also worth
> checking the resolution of wallpaper
> after rotation. Is it at the same quality or is it worse? The cache might be a
> small resolution wallpaper
> which then scaled to fit the height of the rotated screen. If we clear cache,
we
> will load a large resolution
> wallpaper so the quality of wallpaper might be better. It may not make much
> difference but worth checking.

With or without clearing the cache, the result visually is the exact same! I
tried with multiple wallpapers.

[bshe, 2015-05-12 16:53:04]

On 2015/05/12 16:51:32, afakhry wrote:
> On 2015/05/12 13:19:32, bshe wrote:
> > On 2015/05/11 23:41:40, afakhry wrote:
> > > On 2015/05/11 23:41:04, afakhry wrote:
> > > > Hi bshe@, Could you please review this CL?
> > > 
> > > tdanderson@, could you please verify that this is visually acceptable?
> > 
> > Sorry, just remember something as I look at your CL. It would also worth
> > checking the resolution of wallpaper
> > after rotation. Is it at the same quality or is it worse? The cache might be
a
> > small resolution wallpaper
> > which then scaled to fit the height of the rotated screen. If we clear
cache,
> we
> > will load a large resolution
> > wallpaper so the quality of wallpaper might be better. It may not make much
> > difference but worth checking.
> 
> With or without clearing the cache, the result visually is the exact same! I
> tried with multiple wallpapers.

great. Thanks for checking! lgtm

[tdanderson, 2015-05-12 17:49:16]

On 2015/05/12 16:53:04, bshe wrote:
> On 2015/05/12 16:51:32, afakhry wrote:
> > On 2015/05/12 13:19:32, bshe wrote:
> > > On 2015/05/11 23:41:40, afakhry wrote:
> > > > On 2015/05/11 23:41:04, afakhry wrote:
> > > > > Hi bshe@, Could you please review this CL?
> > > > 
> > > > tdanderson@, could you please verify that this is visually acceptable?
> > > 
> > > Sorry, just remember something as I look at your CL. It would also worth
> > > checking the resolution of wallpaper
> > > after rotation. Is it at the same quality or is it worse? The cache might
be
> a
> > > small resolution wallpaper
> > > which then scaled to fit the height of the rotated screen. If we clear
> cache,
> > we
> > > will load a large resolution
> > > wallpaper so the quality of wallpaper might be better. It may not make
much
> > > difference but worth checking.
> > 
> > With or without clearing the cache, the result visually is the exact same! I
> > tried with multiple wallpapers.
> 
> great. Thanks for checking! lgtm

I still can't reproduce with my developer build. I see the same behaviour
with and without the CL. I would say go ahead and land it, and I'll
make a note to examine the behaviour in an official build once
the change makes it into dev-channel.

[afakhry, 2015-05-12 20:56:32]

The CQ bit was checked by afakhry@chromium.org

[commit-bot: I haz the power, 2015-05-12 20:58:43]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1131243006/1

[commit-bot: I haz the power, 2015-05-12 22:19:09]

Committed patchset #1 (id:1)

[commit-bot: I haz the power, 2015-05-12 22:19:56]

Patchset 1 (id:??) landed as
https://crrev.com/7a1ba5ffc2e68bafbeefc80a76b71f6221601712
Cr-Commit-Position: refs/heads/master@{#329507}

[oshima, 2015-05-12 22:36:22]

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

[oshima, 2015-05-12 22:36:23]

https://codereview.chromium.org/1131243006/diff/1/ash/desktop_background/desk...
File ash/desktop_background/desktop_background_controller.cc (right):

https://codereview.chromium.org/1131243006/diff/1/ash/desktop_background/desk...
ash/desktop_background/desktop_background_controller.cc:140:
base::Unretained(this), false /* clear cache */));
Sorry if I wasn't clear. We shouldn't need any delay when rotated with 
accelerometer. Delay was added for when rotating using UI (shortcut / settings).