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, 4 insertions, 4 deletions

diff --git a/js/dispatch_json.ts b/js/dispatch_json.ts
index 8ec924f4c..572ec855a 100644
--- a/js/dispatch_json.ts
+++ b/js/dispatch_json.ts
@@ -1,8 +1,8 @@
 // Copyright 2018-2019 the Deno authors. All rights reserved. MIT license.
-import * as util from "./util";
-import { TextEncoder, TextDecoder } from "./text_encoding";
-import { core } from "./core";
-import { ErrorKind, DenoError } from "./errors";
+import * as util from "./util.ts";
+import { TextEncoder, TextDecoder } from "./text_encoding.ts";
+import { core } from "./core.ts";
+import { ErrorKind, DenoError } from "./errors.ts";
 
 // eslint-disable-next-line @typescript-eslint/no-explicit-any
 type Ok = any;