Update dependencies.

package.json

@@ -30,10 +30,10 @@
     "postpublish": "git push && git push --tags && cd ../d3.github.com && git pull && cp ../${npm_package_name}/dist/${npm_package_name}.js ${npm_package_name}.v${npm_package_version%%.*}.js && cp ../${npm_package_name}/dist/${npm_package_name}.min.js ${npm_package_name}.v${npm_package_version%%.*}.min.js && git add ${npm_package_name}.v${npm_package_version%%.*}.js ${npm_package_name}.v${npm_package_version%%.*}.min.js && git commit -m \"${npm_package_name} ${npm_package_version}\" && git push && cd - && zip -j dist/${npm_package_name}.zip -- LICENSE README.md dist/${npm_package_name}.js dist/${npm_package_name}.min.js"
   },
   "devDependencies": {
-    "eslint": "5",
-    "jsdom": "12",
-    "rollup": "0.64",
-    "rollup-plugin-terser": "1",
+    "eslint": "6",
+    "jsdom": "15",
+    "rollup": "1",
+    "rollup-plugin-terser": "5",
     "tape": "4"
   }
 }

src/namespace.js

@@ -3,5 +3,5 @@ import namespaces from "./namespaces.js";
 export default function(name) {
   var prefix = name += "", i = prefix.indexOf(":");
   if (i >= 0 && (prefix = name.slice(0, i)) !== "xmlns") name = name.slice(i + 1);
-  return namespaces.hasOwnProperty(prefix) ? {space: namespaces[prefix], local: name} : name;
+  return namespaces.hasOwnProperty(prefix) ? {space: namespaces[prefix], local: name} : name; // eslint-disable-line no-prototype-builtins
 }