Avoid srcset resource download when higher density resource is in cache.

Avoid srcset resource download when higher density resource is in cache.

When resizing the viewport, srcset re-evaluates its resources, and downloads
a new one if needed.

However, since srcset is by definition not related to art-direction,
there's no need to download a new resource is there is a higher density one
that's already in the memory cache.

This CL avoids that unneccessary download.

BUG=425701
Committed: https://src.chromium.org/viewvc/blink?view=rev&revision=184335

[Yoav Weiss, 2014-10-23 22:00:36]

yoav@yoav.ws changed reviewers:
+ mkwst@chromium.org

[Mike West, 2014-10-24 05:16:39]

Bot failures look relevant. Happy to take a look at the patch once the bots are
happy. :)

[Yoav Weiss, 2014-10-24 06:08:53]

On 2014/10/24 05:16:39, Mike West wrote:
> Bot failures look relevant. Happy to take a look at the patch once the bots
are
> happy. :)

I think I fixed the bot failures now. Time will tell. :)

[Mike West, 2014-10-24 08:03:13]

LGTM, thanks.

https://codereview.chromium.org/674923004/diff/60001/Source/core/html/parser/...
File Source/core/html/parser/HTMLSrcsetParser.cpp (right):

https://codereview.chromium.org/674923004/diff/60001/Source/core/html/parser/...
Source/core/html/parser/HTMLSrcsetParser.cpp:390: ASSERT(winner <
imageCandidates.size());
&& >= 0?

[Yoav Weiss, 2014-10-24 08:08:00]

On 2014/10/24 08:03:13, Mike West wrote:
> LGTM, thanks.
> 
>
https://codereview.chromium.org/674923004/diff/60001/Source/core/html/parser/...
> File Source/core/html/parser/HTMLSrcsetParser.cpp (right):
> 
>
https://codereview.chromium.org/674923004/diff/60001/Source/core/html/parser/...
> Source/core/html/parser/HTMLSrcsetParser.cpp:390: ASSERT(winner <
> imageCandidates.size());
> && >= 0?

winner is unsigned

[Mike West, 2014-10-24 08:28:48]

On 2014/10/24 08:08:00, Yoav Weiss wrote:
> On 2014/10/24 08:03:13, Mike West wrote:
> > LGTM, thanks.
> > 
> >
>
https://codereview.chromium.org/674923004/diff/60001/Source/core/html/parser/...
> > File Source/core/html/parser/HTMLSrcsetParser.cpp (right):
> > 
> >
>
https://codereview.chromium.org/674923004/diff/60001/Source/core/html/parser/...
> > Source/core/html/parser/HTMLSrcsetParser.cpp:390: ASSERT(winner <
> > imageCandidates.size());
> > && >= 0?
> 
> winner is unsigned

You've thought of everything! Land it.

[Yoav Weiss, 2014-10-24 08:30:43]

The CQ bit was checked by yoav@yoav.ws

[Yoav Weiss, 2014-10-24 08:30:51]

On 2014/10/24 08:28:48, Mike West wrote:
> On 2014/10/24 08:08:00, Yoav Weiss wrote:
> > On 2014/10/24 08:03:13, Mike West wrote:
> > > LGTM, thanks.
> > > 
> > >
> >
>
https://codereview.chromium.org/674923004/diff/60001/Source/core/html/parser/...
> > > File Source/core/html/parser/HTMLSrcsetParser.cpp (right):
> > > 
> > >
> >
>
https://codereview.chromium.org/674923004/diff/60001/Source/core/html/parser/...
> > > Source/core/html/parser/HTMLSrcsetParser.cpp:390: ASSERT(winner <
> > > imageCandidates.size());
> > > && >= 0?
> > 
> > winner is unsigned
> 
> You've thought of everything! Land it.

:D

[commit-bot: I haz the power, 2014-10-24 08:30:55]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/674923004/60001

[commit-bot: I haz the power, 2014-10-24 08:34:31]

Committed patchset #4 (id:60001) as 184335