983478 - Rearranging thumbnails in about:newtab doesn't work

Status: VERIFIED FIXED

(Firefox :: Tabbed Browser, defect)

Description

[obrufau]

User Agent: Mozilla/5.0 (Windows NT 5.1; rv:30.0) Gecko/20100101 Firefox/30.0 (Beta/Release)
Build ID: 20140313030202

Steps to reproduce:

Go to about:newtab, and drag a thumbnail to another position.


Actual results:

While being dragged, thumbnails are rearranged correctly. But when dropping it, instead of appearing where it should, it moves back to its previous position, overlapping the item that has taken its old place.


Expected results:

The dropped item should appear where it has been dropped.

The inappropriate position is caused by `left` and `top` properties of `.newtab-site` element. Removing them moves the dropped item to the appropriate position.

Comment 1

[Alice0775 White]

Regression Window(fx)
Good:
https://hg.mozilla.org/integration/fx-team/rev/a9af498c077d
Mozilla/5.0 (Windows NT 6.1; WOW64; rv:30.0) Gecko/20100101 Firefox/30.0 ID:20140220214528
Bad:
https://hg.mozilla.org/integration/fx-team/rev/5d896e33c6a6
Mozilla/5.0 (Windows NT 6.1; WOW64; rv:30.0) Gecko/20100101 Firefox/30.0 ID:20140221005525
Pushlog:
http://hg.mozilla.org/integration/fx-team/pushloghtml?fromchange=a9af498c077d&tochange=5d896e33c6a6

Regressed by: Bug 895359

Comment 2

[Benjamin Kerensa [:bkerensa]]

Tim, Could you have a look at this?

Comment 3

[obrufau]

The problem is that the rearranged item isn't unfrozen.

It seems that this is what happens when an item is rearranged:

 * gDrop.drop
    * gUpdater.updateGrid
       * gUpdater._freezeSitePositions
 * gDrag.end
    * gTransformation.slideSiteTo with {unfreeze: true}
       * gTransformation.unfreezeSitePosition

But the problem is that gUpdater.updateGrid delays gUpdater._freezeSitePositions, so it runs after gTransformation.unfreezeSitePosition

Comment 5

[Tim Taubert [:ttaubert] (inactive)]

Fixed by backing out bug 895359.

Comment 6

[Tim Taubert [:ttaubert] (inactive)]

Attachment: Backout of bug 895359

[Approval Request Comment]
Bug caused by (feature/regressing bug #): bug 895359
User impact if declined: Dragging tiles on about:newtab is broken for Windows users.
Testing completed (on m-c, etc.): 
Risk to taking this patch (and alternatives if risky): Low risk, straight backout.
String or IDL/UUID changes made by this patch: None.

Comment 7

[Marco Mucci [:MarcoM]]

Hi Anthony, can you review to determine if this bug should be marked as [qa+] or [qa-] for verification.

Comment 8

[u279076]

Ioana, can you please assign this to someone for verification?

Comment 9

[Ioana (away)]

Cornel, please verify this today.

Comment 10

[Cornel Ionce [:noni] [Hubs QA]]

Mozilla/5.0 (Windows NT 5.1; rv:31.0) Gecko/20100101 Firefox/31.0
Mozilla/5.0 (Windows NT 6.1; rv:31.0) Gecko/20100101 Firefox/31.0
Mozilla/5.0 (X11; Linux i686; rv:31.0) Gecko/20100101 Firefox/31.0
Mozilla/5.0 (Macintosh; Intel Mac OS X 10.9; rv:31.0) Gecko/20100101 Firefox/31.0

Verified as fixed on latest Nightly (build ID: 20140326030203).
The thumbnails in about:newtab can now be properly rearranged.

I'll keep an eye on this issue since Firefox 30 is still affected.

Comment 11

[Tim Taubert [:ttaubert] (inactive)]

Bug 895359 has been backed out from Aurora.

Comment 12

[Cornel Ionce [:noni] [Hubs QA]]

Verified fix on latest Aurora, build ID: 20140331004001.