Bug 20892 – Transition starts running when it shouldn't

• Status: RESOLVED
• Resolution: FIXED
• Component: CSS

[Chris Marrin]

Run the attached test case and notice that it fails. This test has an animation and transition on the same property (-webkit-transform). The transition is never started, it's property is never changed. But when the animation starts, the AnimationController thinks the transition should start, because the animation starts changing the property.

The fix is to have the animation remember the style just before it started and use that to test the transition against. Patch is attached.

[Chris Marrin]

Created attachment 23491 [details]
test case showing bug

[Chris Marrin]

Created attachment 23492 [details]
Patch, including LayoutTest file

[Dave Hyatt]

Comment on attachment 23492 [details]
Patch, including LayoutTest file

r=me

[Chris Marrin]

The fix is basically to save the unanimated style when an animation is started, in that animation. Then, when starting a transition, I check to see if there is a current animation on the same prop. If so, I use the unanimated style as the fromStyle rather than the current style.

[Dean Jackson]

Committed r36687
	M	WebCore/ChangeLog
	M	WebCore/page/animation/ImplicitAnimation.h
	M	WebCore/page/animation/CompositeAnimation.cpp
	M	WebCore/page/animation/KeyframeAnimation.cpp
	M	WebCore/page/animation/CompositeAnimation.h
	M	WebCore/page/animation/KeyframeAnimation.h
	M	WebCore/page/animation/ImplicitAnimation.cpp
	M	LayoutTests/ChangeLog
	A	LayoutTests/animations/transition-and-animation-1-expected.txt
	A	LayoutTests/animations/transition-and-animation-1.html