Since Keyframe.easing should reflect the {transition,animation}-timing-
function value relevant to each keyframe, we'll need to store on
nsTimingFunction the specific timing function value that was used, and
copy it down into ComputedTimingFunction for
KeyframeEffectReadOnly.getFrames() to access. This includes storing
whether the optional start/end keyword in a steps() function was
specified.
The change breaks some scenarios with APZ scrolling, in particular the code
that layerizes the scroll handoff chain for deeply nested scrollable frames.
Also...
- Rename various "operator" identifiers as "op" to match |CompositionOp|.
- Rename |nsBackgroundLayerState::mCompositingOp| as |mCompositionOp| to match
|CompositionOp|.
- Remove some deprecated functions that are no longer needed.
Remove WrapPreserve3DList() and replaced it by creating a
nsDisplayTransform item for each transformed frame.
- Add an additional item for each top frame extending 3D context to
separate consequence contexts.
- Effective transform of a layer is the accumulation of ancestors in
the same 3D context.
- The layers creating new context and extended by children need a
temporary buffer if it's effective transform is not 2D.
- Clip rects are accumulated along the context chain.
- Visible rects of items are computed from dirty regions of the frame
creating the context and accumulated transforms.
- Bounds of items are computed from accumulated transforms and
accumulated bounds of the descent frames.
- Backface hidden is handled by compositor and BasicLayerManager.
Remove WrapPreserve3DList() and replaced it by creating a
nsDisplayTransform item for each transformed frame.
- Add an additional item for each top frame extending 3D context to
separate consequence contexts.
- Effective transform of a layer is the accumulation of ancestors in
the same 3D context.
- The layers creating new context and extended by children need a
temporary buffer if it's effective transform is not 2D.
- Clip rects are accumulated along the context chain.
- Visible rects of items are computed from dirty regions of the frame
creating the context and accumulated transforms.
- Bounds of items are computed from accumulated transforms and
accumulated bounds of the descent frames.
- Backface hidden is handled by compositor and BasicLayerManager.
This is in anticipation of adding Animation::SetTimeline(). Once we set the
timeline out of band, there's a chance that getting it could return null so
this patch makes the WebIDL and method name reflect that.
This is not strictly necessary yet but we will want to implement methods
like GetAnimations() on the base class, AnimationTimeline, so we may as well do
that now rather than adding that code to DocumentTimeline and moving it later.
For regular, display list based, hit testing viewport frames never add any items to the display list. So are never "hit". Layer event regions should follow this same path.
The code that this replaces was a partial, incorrect, fix for this problem (from bug 1121033).