Rollup is a moving target, perhaps we should submodule it instead of adding so many files.

I have a try for as rollup as git submodules, here has some problems.

• rollup test runner(utils.js) and test case depend on the runner(require some method from runner), so I meet crash at run rollup test using custom runner. It means we need port test cases and using custom runner.
• rollup test runner need a lot of node_modules dependencies, which has some post-install package, eg esbuild/puppeteer,etc.So it look like isn't a clean way if we use it as test runner.