launcher icon animation end with a dirty black artifact

[Y.Gicquel]

[Impact]

 * While launching an application, the icon animation (zoom & transparency) end with a black transient frame. ( See video attached which highlight this "black frame" artifact. )

 * Issue due to buffer destruction before window. Correction consist of hiding window before buffer destruction and avoid random display on screen.

 * SRU request for this correction to avoid displaying a destroyed buffer on screen, and enhance end user experience.

[Test Case]

 * just click on icon in panel. (see video)

[Regression Potential]

 * correction in a dedicated function of gnome-panel, for animation stuffs.

 * without this patch, buffer is destroy before window destruction; meaning that Gtk framework continue to access memory buffer area which is not valid anymore...

[Other Info]

 * A bug has been opened in gnome-panel bugzilla for upstream developers : https://bugzilla.gnome.org/show_bug.cgi?id=688618

 * Observed on gnome-panel version 3.4.1 ( current version in precise ) but issue is still present in trunk release in upstream version as well.

 * Bug affect users using a compositing window manager configuration ( other dedicated code is used for other cases )

Regards,

[Y.Gicquel (yannick-gicquel)]

Issue root cause is destruction of overlayed window's pixbuf before hiding it.
Attached patched correct the behavior hiding the animation window before destroying its content.

[Ubuntu Foundations Team Bug Bot (crichton)]

The attachment "90-remove_artifact_on_icon_animation.patch" of this bug report has been identified as being a patch. The ubuntu-reviewers team has been subscribed to the bug report so that they can review the patch. In the event that this is in fact not a patch you can resolve this situation by removing the tag 'patch' from the bug report and editing the attachment so that it is not flagged as a patch. Additionally, if you are member of the ubuntu-reviewers team please also unsubscribe the team from this bug report.

[This is an automated message performed by a Launchpad user owned by Brian Murray. Please contact him regarding any issues with the action taken in this bug report.]

[Sebastien Bacher (seb128)]

gnome-panel (1:3.6.2-0ubuntu2) raring; urgency=low

  * debian/patches/90-remove_artifact_on_icon_animation.patch:
    + Remove black frame artifact on launcher icon zoom animation.