[SVGDom] Add viewBox support

The main feature is <svg> viewBox and proper viewport support, but the CL
touches a few other things:

* refactor SkSVGRenderContext to auto-restore canvas state, and split the
  presentation bits into a separate CoW SkSVGPresentationContext

* introduce SkSVGNode::onPrepareToRender(), as a way for nodes to push their
  custom state before the actual onRender() call (instead of relying on
  non-virtual SkSVGNode to know about all possible state bits)

* add a "Type" suffix to SVG types, to disambiguate (e.g. SkSVGRectType vs.
  SkSVGRect)

R=robertphillips@google.com,stephana@google.com
GOLD_TRYBOT_URL= https://gold.skia.org/search?issue=2222793002

Review-Url: https://codereview.chromium.org/2222793002

1 files changed, 1 insertions, 7 deletions

diff --git a/experimental/svg/model/SkSVGRect.cpp b/experimental/svg/model/SkSVGRect.cpp
index 288fc48258..b65c2b9974 100644
--- a/experimental/svg/model/SkSVGRect.cpp
+++ b/experimental/svg/model/SkSVGRect.cpp
@@ -58,11 +58,5 @@ void SkSVGRect::onSetAttribute(SkSVGAttribute attr, const SkSVGValue& v) {
 
 void SkSVGRect::onDraw(SkCanvas* canvas, const SkSVGLengthContext& lctx,
                        const SkPaint& paint) const {
-    const SkRect r = SkRect::MakeXYWH(
-        lctx.resolve(fX, SkSVGLengthContext::LengthType::kHorizontal),
-        lctx.resolve(fY, SkSVGLengthContext::LengthType::kVertical),
-        lctx.resolve(fWidth, SkSVGLengthContext::LengthType::kHorizontal),
-        lctx.resolve(fHeight, SkSVGLengthContext::LengthType::kVertical));
-
-    canvas->drawRect(r, paint);
+    canvas->drawRect(lctx.resolveRect(fX, fY, fWidth, fHeight), paint);
 }