[SVGDom] Expose intrinsic size info

experimental/svg/model/SkSVGDOM.cpp

 /*
  * Copyright 2016 Google Inc.
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 #include "SkCanvas.h"
 #include "SkDOM.h"
 #include "SkParsePath.h"
@@ skipping 366 matching lines @@
         if (childNode) {
             node->appendChild(std::move(childNode));
         }
     }
 
     return node;
 }
 
 } // anonymous namespace
 
-SkSVGDOM::SkSVGDOM(const SkSize& containerSize)
-    : fContainerSize(containerSize) {
+SkSVGDOM::SkSVGDOM()
+    : fContainerSize(SkSize::Make(0, 0)) {
 }
 
-sk_sp<SkSVGDOM> SkSVGDOM::MakeFromDOM(const SkDOM& xmlDom, const SkSize& containerSize) {
-    sk_sp<SkSVGDOM> dom = sk_make_sp<SkSVGDOM>(containerSize);
+sk_sp<SkSVGDOM> SkSVGDOM::MakeFromDOM(const SkDOM& xmlDom) {
+    sk_sp<SkSVGDOM> dom = sk_make_sp<SkSVGDOM>();
 
     ConstructionContext ctx(&dom->fIDMapper);
     dom->fRoot = construct_svg_node(xmlDom, ctx, xmlDom.getRootNode());
 
+    // Reset the default container size to match the intrinsic SVG size.
+    dom->setContainerSize(dom->intrinsicSize());
+
     return dom;
 }
 
-sk_sp<SkSVGDOM> SkSVGDOM::MakeFromStream(SkStream& svgStream, const SkSize& containerSize) {
+sk_sp<SkSVGDOM> SkSVGDOM::MakeFromStream(SkStream& svgStream) {
     SkDOM xmlDom;
     if (!xmlDom.build(svgStream)) {
         return nullptr;
     }
 
-    return MakeFromDOM(xmlDom, containerSize);
+    return MakeFromDOM(xmlDom);
 }
 
 void SkSVGDOM::render(SkCanvas* canvas) const {
     if (fRoot) {
         SkSVGRenderContext ctx(canvas,
                                fIDMapper,
                                SkSVGLengthContext(fContainerSize),
                                SkSVGPresentationContext());
         fRoot->render(ctx);
     }
 }
 
+SkSize SkSVGDOM::intrinsicSize() const {
+    if (!fRoot || fRoot->tag() != SkSVGTag::kSvg) {
+        return SkSize::Make(0, 0);
+    }
+
+    // Intrinsic sizes are never relative, so the viewport size is irrelevant.
+    const SkSVGLengthContext lctx(SkSize::Make(0, 0));
+    return static_cast<const SkSVGSVG*>(fRoot.get())->intrinsicSize(lctx);
+}
+
+const SkSize& SkSVGDOM::containerSize() const {
+    return fContainerSize;
+}
+
 void SkSVGDOM::setContainerSize(const SkSize& containerSize) {
     // TODO: inval
     fContainerSize = containerSize;
 }
 
 void SkSVGDOM::setRoot(sk_sp<SkSVGNode> root) {
     fRoot = std::move(root);
 }