Bug 142517

Summary: Assertion in ScrollController::processWheelEventForScrollSnapOnAxis when scrolling with mechanical wheel mouse
Product: WebKit Reporter: Brent Fulgham <bfulgham>
Component: Layout and RenderingAssignee: Brent Fulgham <bfulgham>
Status: RESOLVED FIXED    
Severity: Normal CC: bfulgham, webkit-bug-importer
Priority: P2 Keywords: InRadar
Version: 528+ (Nightly build)   
Hardware: All   
OS: All   
Attachments:
Description Flags
Patch
none
Patch simon.fraser: review+

Description Brent Fulgham 2015-03-09 17:32:50 PDT 
In Bug 141973 (<https://trac.webkit.org/changeset/180987>) I introduced a regression for mechanical wheel mice users. After my change, WebKit always creates a snap scroll animation state context, which triggers new scroll snap point logic when processing wheel events.

If you work with a mechanical wheel mouse, the scroll snap point handler does not understand the gesture (since mechanical mice only produce "stateless" wheel events), and complains via an assertion.
Comment 1 Brent Fulgham 2015-03-09 17:33:17 PDT 
<rdar://problem/20088167>
Comment 2 Brent Fulgham 2015-03-09 17:35:35 PDT 
Note: additional work for mechanical wheel mice is being done under Bug 142501.
Comment 3 Brent Fulgham 2015-03-09 17:38:09 PDT 
Created attachment 248301 [details]
Patch
Comment 4 Brent Fulgham 2015-03-09 17:47:16 PDT 
Created attachment 248302 [details]
Patch
Comment 5 Brent Fulgham 2015-03-09 18:00:41 PDT 
Committed r181300: <http://trac.webkit.org/changeset/181300>