Remove special touch-action hit test mode

Remove special touch-action hit test mode

Don't try to mimic IE's special hit-testing behavior for touch-action - it probably only adds confusion and is unlikely to cause compat issues in practice.  See http://crbug.com/380203 for details.

Also reduces the hit tests done on touchstart from 2 to 1 for improved performance.

BUG=380203
Committed: https://src.chromium.org/viewvc/blink?view=rev&revision=176285

[Rick Byers, 2014-06-11 12:52:01]

This is looking good, thanks!

https://codereview.chromium.org/329773002/diff/1/Source/core/rendering/Render...
File Source/core/rendering/RenderObject.cpp (left):

https://codereview.chromium.org/329773002/diff/1/Source/core/rendering/Render...
Source/core/rendering/RenderObject.cpp:3319: // touch-action applies to all
elements with both width AND height properties.
We need to keep this logic (and comment) somewhere, the only real change is that
instead of "visible for touch action" it's more of a "supports touch action".  I
think leaving it on RenderObject (but renamed, eg "supportsTouchAction") is
probably best (although it could also be kept in EventHandler now I think).

[gnana, 2014-06-12 14:02:08]

Please have a look.
Do i need to add more in discription.

https://codereview.chromium.org/329773002/diff/40001/Source/core/page/EventHa...
File Source/core/page/EventHandler.cpp (right):

https://codereview.chromium.org/329773002/diff/40001/Source/core/page/EventHa...
Source/core/page/EventHandler.cpp:3633: if (node.renderer() &&
!node.renderer()->supportsTouchAction())
This check is added for below testcase.

<div class='ta-none' style='height: 0; margin-bottom: 50px'>
  <span expected-action='auto'>
    touch-action should not be inherited by inline elements
  </span>
</div>

[Rick Byers, 2014-06-12 19:27:25]

Thanks for doing this Gnana.  This is almost right.  The key behavior change
here is that elements without width/height that overflow the bounds of their
parent will now still use their parent's touch-action.

Note that a number of other tests (all the "should be inherited by" ones) were
designed with this special hit test in mind (by making them escape outside the
bounds of their ancestor).  I don't think it hurts to leave them though (even
though they're not as relevant anymore) - it shows that we're really only
changing behavior in this one special case.

I'll update the description of the CL slightly - the details are all in the bug.

https://codereview.chromium.org/329773002/diff/40001/Source/core/page/EventHa...
File Source/core/page/EventHandler.cpp (right):

https://codereview.chromium.org/329773002/diff/40001/Source/core/page/EventHa...
Source/core/page/EventHandler.cpp:3633: if (node.renderer() &&
!node.renderer()->supportsTouchAction())
On 2014/06/12 14:02:08, gnana wrote:
> This check is added for below testcase.
> 
> <div class='ta-none' style='height: 0; margin-bottom: 50px'>
>   <span expected-action='auto'>
>     touch-action should not be inherited by inline elements
>   </span>
> </div>

This is the case we need to change the test for.  Remove this code (it'll break
common cases like inline text inside of a DIV that has touch-action applied).

This test case should be updated to say "SHOULD BE inherited by inline elements"
and I'd explicitly add something like "(note this is different than IE, see
http://crbug.com/380203)".

[gnana, 2014-06-13 09:28:54]

Please have a look.

[Rick Byers, 2014-06-13 20:45:40]

LGTM, thanks.

+aelias for OWNERS in Source/web for the test update

https://codereview.chromium.org/329773002/diff/60001/Source/web/tests/data/to...
File Source/web/tests/data/touch-action-simple.html (right):

https://codereview.chromium.org/329773002/diff/60001/Source/web/tests/data/to...
Source/web/tests/data/touch-action-simple.html:44: touch-action should be
inherited by inline elements.<br>Note this is different than
IE(http://crbug.com/380203)
nit: space before (

[gnana, 2014-06-16 05:20:48]

Please have a look.
+aelias for OWNERS in Source/web for the test update

https://codereview.chromium.org/329773002/diff/60001/Source/web/tests/data/to...
File Source/web/tests/data/touch-action-simple.html (right):

https://codereview.chromium.org/329773002/diff/60001/Source/web/tests/data/to...
Source/web/tests/data/touch-action-simple.html:44: touch-action should be
inherited by inline elements.<br>Note this is different than
IE(http://crbug.com/380203)
On 2014/06/13 20:45:40, Rick Byers wrote:
> nit: space before (

Done.

[aelias_OOO_until_Jul13, 2014-06-17 02:32:35]

lgtm for Source/web

[gnana, 2014-06-17 04:57:20]

The CQ bit was checked by gnanasekar.s@samsung.com

[commit-bot: I haz the power, 2014-06-17 04:58:22]

CQ is trying da patch. Follow status at
 https://chromium-status.appspot.com/cq/gnanasekar.s@samsung.com/329773002/80001

[commit-bot: I haz the power, 2014-06-17 06:07:14]

Change committed as 176285