Refactor snapshot build (#2825)

Instead of using core/snapshot_creator.rs, instead two crates are
introduced which allow building the snapshot during build.rs.

Rollup is removed and replaced with our own bundler. This removes
the Node build dependency. Modules in //js now use Deno-style imports
with file extensions, rather than Node style extensionless imports.

This improves incremental build time when changes are made to //js files
by about 40 seconds.

1 files changed, 7 insertions, 7 deletions

diff --git a/js/process.ts b/js/process.ts
index dd4f70103..4de9fe774 100644
--- a/js/process.ts
+++ b/js/process.ts
@@ -1,11 +1,11 @@
 // Copyright 2018-2019 the Deno authors. All rights reserved. MIT license.
-import { sendSync, sendAsync } from "./dispatch_json";
-import * as dispatch from "./dispatch";
-import { File, close } from "./files";
-import { ReadCloser, WriteCloser } from "./io";
-import { readAll } from "./buffer";
-import { assert, unreachable } from "./util";
-import { platform } from "./build";
+import { sendSync, sendAsync } from "./dispatch_json.ts";
+import * as dispatch from "./dispatch.ts";
+import { File, close } from "./files.ts";
+import { ReadCloser, WriteCloser } from "./io.ts";
+import { readAll } from "./buffer.ts";
+import { assert, unreachable } from "./util.ts";
+import { platform } from "./build.ts";
 
 /** How to handle subprocess stdio.
  *