fix(core/figures): don't add width/height to .svg images (speced#4422)

src/core/figures.js

@@ -126,7 +126,13 @@ function normalizeImages(doc) {
       ":not(picture)>img:not([width]):not([height]):not([srcset])"
     )
     .forEach(img => {
+      // Don't add width and height to SVGs
+      // https://github.com/w3c/respec/issues/3435
+      if (img.src.startsWith("data:image/svg+xml;")) return;
+      if (img.src.endsWith(".svg")) return;
+
       if (img.naturalHeight === 0 || img.naturalWidth === 0) return;
+
       img.height = img.naturalHeight;
       img.width = img.naturalWidth;
     });

tests/spec/core/figures-spec.js

@@ -137,6 +137,8 @@ describe("Core - Figures", () => {
          <img id="image-with-height-only" height=100 src="${imgDataURL}">
          <img id="image-with-width-only" width=200 src="${imgDataURL}">
          <img id="image-with-srcset" srcset="${imgDataURL}">
+         <img id="image-svg-url" src="/img/foo.svg">
+         <img id="image-svg-data-uri" src="data:image/svg+xml,<svg xmlns="http://www.w3.org/2000/svg"/>">
          <picture>
           <img id="image-inside-picture" src="${imgDataURL}">
          </picture>
@@ -192,6 +194,18 @@ describe("Core - Figures", () => {
       expect(image.hasAttribute("height")).toBeFalsy();
       expect(image.hasAttribute("width")).toBeFalsy();
     });
+
+    it("doesn't set height or width to SVG images", async () => {
+      const imageSvgUrl = doc.getElementById("image-svg-url");
+      expect(imageSvgUrl).toBeTruthy();
+      expect(imageSvgUrl.hasAttribute("height")).toBeFalsy();
+      expect(imageSvgUrl.hasAttribute("width")).toBeFalsy();
+
+      const imageSvgDataUri = doc.getElementById("image-svg-data-uri");
+      expect(imageSvgDataUri).toBeTruthy();
+      expect(imageSvgDataUri.hasAttribute("height")).toBeFalsy();
+      expect(imageSvgDataUri.hasAttribute("width")).toBeFalsy();
+    });
   });
   it("localizes list of figures", async () => {
     const ops = {