Bug 1004871 part 10 - Stop passing a fill mode of "both" to GetComputedTimingAt for throttled samples; r=dholbert

This was only needed when we were inspecting the returned time fraction but now
that we inspect the phase it's not necessary to force the fill mode to "both".

layout/style/nsAnimationManager.cpp

@@ -76,10 +76,8 @@ ElementAnimations::EnsureStyleRuleFor(TimeStamp aRefreshTime,
       // The ElapsedDurationAt() call here handles pausing.  But:
       // FIXME: avoid recalculating every time when paused.
       TimeDuration elapsedDuration = anim->ElapsedDurationAt(aRefreshTime);
-      AnimationTiming timing = anim->mTiming;
-      timing.mFillMode = NS_STYLE_ANIMATION_FILL_MODE_BOTH;
       ComputedTiming computedTiming =
-        ElementAnimation::GetComputedTimingAt(elapsedDuration, timing);
+        ElementAnimation::GetComputedTimingAt(elapsedDuration, anim->mTiming);
 
       // XXX We shouldn't really be using mLastNotification as a general
       // indicator that the animation has finished, it should be reserved for