Inherit Presentation role only when elements without a explicit role defined.

Inherit Presentation role only when elements without a explicit role defined.

The presentation role can be inherited to owned children
only when it doesn't a implicit role defined.
AXRenderObject::inheritsPresentationalRole() is used to check that
the presentation role can be inherited or not.
This patch added checking if element has a explicit role defined
to AXRenderObject::inheritsPresentationalRole().
The related spec,
http://www.w3.org/TR/wai-aria/roles#presentation.

BUG=447994
Committed: https://src.chromium.org/viewvc/blink?view=rev&revision=188479

[je_julie(Not used), 2015-01-15 10:28:10]

je_julie.kim@samsung.com changed reviewers:
+ dmazzoni@chromium.org

[je_julie(Not used), 2015-01-15 10:35:55]

Hi Dominic,

This patch makes presentation role can be inherited
only when element doesn't have a explicit role defined.
While investigating this issue, I thought that
we need to improve AXRenderObject::inheritsPresentationalRole()
in order to check required owned element.
Currently it checks listitem and listmarker but there are
more required owned element relation with various elements. 
So, I'm thinking of making another patch to improve it.
WDYT?
Please take a look at this patch.

Thanks,

[dmazzoni, 2015-01-15 16:05:29]

The CQ bit was checked by dmazzoni@chromium.org

[dmazzoni, 2015-01-15 16:05:30]

lgtm

Sounds great, this change looks good and it'd be great to follow it up with a
fix for all of the owned element relations.

It'd be great if the definitive list of owned relations was in one place, too.

https://codereview.chromium.org/856473002/diff/1/LayoutTests/accessibility/li...
File LayoutTests/accessibility/listitem-presentation-inherited.html (right):

https://codereview.chromium.org/856473002/diff/1/LayoutTests/accessibility/li...
LayoutTests/accessibility/listitem-presentation-inherited.html:3: <li
role="listitem">Item 1</li>
nit: could you indent the <li> elements inside the <ul> to make this easier to
read?

[commit-bot: I haz the power, 2015-01-15 16:05:44]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/856473002/1

[commit-bot: I haz the power, 2015-01-15 17:15:51]

Committed patchset #1 (id:1) as
https://src.chromium.org/viewvc/blink?view=rev&revision=188479