Bug 59042

Summary: REGRESSION (WK2): Animated GIF stops when navigating forward, back
Product: WebKit Reporter: Andy Estes <aestes>
Component: WebKit2Assignee: Andy Estes <aestes>
Status: RESOLVED FIXED    
Severity: Normal CC: abarth, aestes, eric, webkit.review.bot
Priority: P2 Keywords: InRadar, Regression
Version: 528+ (Nightly build)   
Hardware: PC   
OS: OS X 10.5   
Bug Depends on:    
Bug Blocks: 59062    
Attachments:
Description Flags
Patch mjs: review+

Description Andy Estes 2011-04-20 17:02:04 PDT 
* SUMMARY
After loading this page and going forward, then back, the animated gif stops animating.

* STEPS TO REPRODUCE
1. Load http://en.wikipedia.org/wiki/Methadone
2. Click the animated gif
3. Hit the back button

* RESULTS
Gif no longer animates.
Comment 1 Andy Estes 2011-04-20 17:02:23 PDT 
<rdar://problem/9228639>
Comment 2 Andy Estes 2011-04-20 17:03:31 PDT 
When loading the page from the b/f cache, document()->view()->isOffscreen() returns true in RenderObject::willRenderImage(), so BitmapImage::startAnimation() returns without actually kicking off the animation.

In WebKit1, the ScrollView is a platform widget, so ScrollView::isOffscreen() calls [NSWindow isVisible]. In WebKit2, the ScrollView isn't a platform widget so it asks the WebCore Widget whether or not it is visible. It always returns false since setParentVisible(false) was called on the old ScrollView before navigating to a new page, but setParentVisible(true) is never called when restoring it from the back/forward cache.
Comment 3 Andy Estes 2011-04-20 17:06:14 PDT 
It's sad that I'm fixing a WebKit2-specific bug that'll have to be skipped for now on the WebKit2 bots due to <https://bugs.webkit.org/show_bug.cgi?id=42197> :(
Comment 4 Andy Estes 2011-04-20 17:15:03 PDT 
Created attachment 90450 [details]
Patch
Comment 5 Maciej Stachowiak 2011-04-20 17:31:39 PDT 
Comment on attachment 90450 [details]
Patch

r=me
Comment 6 Andy Estes 2011-04-20 17:46:49 PDT 
Committed r84443: <http://trac.webkit.org/changeset/84443>
Comment 7 WebKit Review Bot 2011-04-20 18:37:05 PDT 
http://trac.webkit.org/changeset/84443 might have broken Windows 7 Release (Tests)
The following tests are not passing:
fast/images/animated-gif-restored-from-bfcache.html