Bug 81187 – Platforms without USE(REQUEST_ANIMATION_FRAME_DISPLAY_MONITOR) don't need to query the page's displayID

• Component: New Bugs
• Status: RESOLVED FIXED

[James Robinson]

Platforms without USE(REQUEST_ANIMATION_FRAME_DISPLAY_MONITOR) don't need to query the page's displayID

[James Robinson]

Created attachment 131980 [details]
Patch

[James Robinson]

In r97405 Chris Marrin added a PlatformDisplayID parameter to ScriptedAnimationController::create(). This is only used if USE(REQUEST_ANIMATION_FRAME_DISPLAY_MONITOR) is set, which is only set on mac and blackberry (?).  Unfortunately this code tries to grab the display ID from Document::page() whenever a callback is set, bug that's not correct - the page() on a Document might be NULL.  We have crash reports in chromium from this exact situation.  Having the display ID on a Document-owned object seems inherently a bit broken - Documents aren't always associated with a Page and can move between Pages.

I had a patch series underway in https://bugs.webkit.org/show_bug.cgi?id=74165 to move the controller up to the Page, which I think will make it clearer how to deal with issues like this.  I haven't had time to get around to this, but this patch avoids doing the unnecessary call (and resulting crash) on most platforms.

[Simon Fraser (smfr)]

Comment on attachment 131980 [details]
Patch

Can you please file a separate bug on page() possibly being null?

[James Robinson]

https://bugs.webkit.org/show_bug.cgi?id=81189

[James Robinson]

Committed r110821: <http://trac.webkit.org/changeset/110821>