REGRESSION (r53110): Find My iPhone message dialog is offset from original position once it gets focus

• Component: Plug-ins
• Status: RESOLVED FIXED

[Adele Peterson]

Steps to reproduce:

1) You must have Find My iPhone enabled with a MobileMe account.
2) Go to me.com, click on Account Settings, and select "Find my iPhone"
3) Click on the button to display a message on your iPhone
4) Click in the textarea

Observe that the dialog and overlay end up significantly offset from the original position

<rdar://problem/7549496>

[Adele Peterson]

This was caused by http://trac.webkit.org/changeset/53109

[Darin Adler]

First thing I would try is to revert that patch and set m_loadManually to NP_FULL in the constructor and see what that does.

[Darin Adler]

Second thing I would try is to revert the patch and set m_loadManually to NP_EMBED in the constructor and see what that does.

[Adele Peterson]

I'm running into an unrelated assertion on this page in debug WebKit.  So I'll try commenting out the assert to try your suggestions.

[Adele Peterson]

My regression testing was off by one.  This was actually caused by r53110

[Simon Fraser (smfr)]

Yeah, that's me.

[Simon Fraser (smfr)]

Created attachment 47211 [details]
Reduced testcase

[Simon Fraser (smfr)]

Filed bug 34009 on avoiding compositing mode just for a 0x0 plugin.

[Simon Fraser (smfr)]

The issue here is that there's a fixed position div inside an abs. position div, and the fixed position div is using the wrong offsets.

In general, there's a conflict between the geometry and layering hierarchies for fixed position elements. In terms of geometry, a fixed layer would naturally be anchored at the root, but in terms of layering it should be anchored in its container.

Layering comes first, but we'll have to throw animations of things with fixed descendants into software.

[Simon Fraser (smfr)]

Created attachment 47230 [details]
Patch

[Simon Fraser (smfr)]

Filed bug 34012 on animating fixed position containers.

Comment on attachment 47230 [details]
Patch

> +        RenderLayer* currLayer = parent();
> +        while (currLayer) {
> +            if (currLayer == ancestorLayer)
> +                foundAncestor = true;
> +
> +            if (isFixedPositionedContainer(currLayer)) {
> +                fixedPositionContainerLayer = currLayer;
> +                ASSERT(foundAncestor);
> +                break;
> +            }
> +            
> +            currLayer = currLayer->parent();
> +        }

Can be written as a for loop with currLayer in the scope of the loop.

[Simon Fraser (smfr)]

http://trac.webkit.org/changeset/53742