Change behaviour of Alt text.

Change behaviour of Alt text.

Alt text to be displayed, when source image is not found,
instead of broken image. Broken image is displayed only if alt
text is not there.

This behaviour is same as Firefox.

BUG=773

[deepak.sa, 2014-06-10 14:09:11]

Please have a look!

This behaviour may not be correct, but it is same as Firefox. So, if another
behaviour is required, that can be looked into.

For now, i have added the platform specific layout test. I am not able to
replicate outer box, which is drawn when image is not found. As soon as, i
replicate that i'll upload RefTest for the same.

Thanks!

[deepak.sa, 2014-06-12 06:37:31]

Layout tests will be failing as there is change in behaviour of alt. These are
failing because it is not showing broken image if alt text is there. I'll update
the layout test cases if this approach is correct. Thanks!

[esprehn, 2014-06-13 05:48:10]

This lgtm, you'll need to rebaseline a lot of tests though. :)

[deepak.sa, 2014-06-18 12:33:26]

On 2014/06/13 05:48:10, esprehn wrote:
> This lgtm, you'll need to rebaseline a lot of tests though. :)

Thanks for the review.
I'll update layout test cases, as soon as possible.

[deepak.sa, 2014-06-30 15:11:58]

Please have another look. Thanks!

[deepak.sa, 2014-07-04 08:04:30]

Rebaselined. Please review.

[deepak.sa, 2014-07-07 04:42:36]

Layout test cases that are failing now are under virtual folder on windows and
mac i.e they are failing under some flags. Even the test case that i have added
is failing under "--enable-deferred-image-decoding" flag. Can you provide some
pointers on how to fix these type of failures?
Thanks!

[deepak.sa, 2014-07-16 15:54:17]

PTAL?
Thanks!

[deepak.sa, 2014-07-21 05:23:26]

Ping!

[esprehn, 2014-07-21 21:45:15]

What's different in LayoutTests/fast/forms/002-expected.png and some of the
other tests? They look the same to me.

[deepak.sa, 2014-07-23 05:40:24]

On 2014/07/21 21:45:15, esprehn wrote:
> What's different in LayoutTests/fast/forms/002-expected.png and some of the
> other tests? They look the same to me.

The main difference is that now alt text is given preference instead of broken
image. So if alt text is there, we'll show alt text, otherwise broken image.

[shreeramk, 2014-07-23 10:55:36]

@deepak.sa

You mentioned in description of this code review that, "Alt text to be
displayed, when source image is not found, instead of broken image. Broken image
is displayed only if alt text is not there."

But I think your changes are not satisfying the description that you have
mentioned.

Suppose in a content, the <img> tag has been specified with a width smaller than
the alt Text width, in that scenario your changes will show a broken image
instead of alt Text. I think that is not correct behaviour, when alt Text is
present, it should display the alt text.

Following content can be considered for testing the behaviour that I mentioned.

<div>
    <img src="imagenotpresent.jpg" width=100px alt="Some long text more than the
size specified in the width attribute then its showing the broken image instead
of the alt text, Please check this behaviour. To me it looks wrong" />
</div>

[deepak.sa, 2014-07-28 14:25:16]

On 2014/07/23 10:55:36, shreeram.k wrote:
> @deepak.sa
> 
> You mentioned in description of this code review that, "Alt text to be
> displayed, when source image is not found, instead of broken image. Broken
image
> is displayed only if alt text is not there."
> 
> But I think your changes are not satisfying the description that you have
> mentioned.
> 
> Suppose in a content, the <img> tag has been specified with a width smaller
than
> the alt Text width, in that scenario your changes will show a broken image
> instead of alt Text. I think that is not correct behaviour, when alt Text is
> present, it should display the alt text.
> 
> Following content can be considered for testing the behaviour that I
mentioned.
> 
> <div>
>     <img src="imagenotpresent.jpg" width=100px alt="Some long text more than
the
> size specified in the width attribute then its showing the broken image
instead
> of the alt text, Please check this behaviour. To me it looks wrong" />
> </div>

@shreeram.k 
Thanks for your elaborate explanation. But this patch only makes Alt text
preferable over broken image. It does not handles the case where alt text length
is bigger than specified length. The issue you described can be handled in
different patch.

@esprehn
PING!

[deepak.sa, 2014-08-01 12:18:11]

shreeram.k will be taking care of this issue in
https://codereview.chromium.org/419453003