[svg] Add several skeleton classes for filters
Added:
- SkSVGFilter: This corresponds to a <filter> element. Also added some
of the attributes of this element.
- SkSVGFe: This will be the base class of all <fe*> elements.
- SkSVGFilterContext: This will hold the contextual mapping of string id
-> image filter result, for constructing pipelines.
Bug: skia:10841
Change-Id: I15a29d39411a6255ab4e11f022baa10554b2bce6
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/330618
Commit-Queue: Tyler Denniston <tdenniston@google.com>
Reviewed-by: Florin Malita <fmalita@chromium.org>
10 files changed
