Revert "Build: fix test failure on Node 11 (#11100)"

tests/lib/util/npm-utils.js

@@ -162,15 +162,8 @@ describe("npmUtils", () => {
         });
 
         it("should return false if package.json does not exist", () => {
-
-            /*
-             * Checking local file system directly, which does not
-             * contains package.json. This is necessary because mock-fs
-             * doesn't work in Node.js 11: it throws an error when
-             * a file is missing rather than returning false.
-             * TODO: Find a replacement for mock-fs that works in Node 11.
-             */
-            assert.strictEqual(npmUtils.checkPackageJson("/"), false);
+            mockFs({});
+            assert.strictEqual(npmUtils.checkPackageJson(), false);
         });
     });