Move ReferenceFilterBuilder::build to FilterEffectBuilder
This function resolves a filter reference and then builds a filter
(sub)DAG for painting. Split it into the two fairly distinct parts,
leaving ReferenceFilterBuilder as a class that only does element
lookup/resolution, while the DAG-building takes place in
FilterEffectBuilder (with a little help from SVGFilterBuilder.)
Use the new function in SVGFilterPainter.
Also pass Element& to ReferenceFilterBuilder::build, and remove a
redundant null-check of ComputedStyle in
PaintLayer::updateOrRemoveFilterEffectBuilder (already checked by
paintsWithFilters and assumed later in the function.)
BUG=109224,533457
Review-Url: https://codereview.chromium.org/2044153002
Cr-Commit-Position: refs/heads/master@{#398866}
6 files changed
