Reduce size of TypeScript Compiler snapshot (#6809)

This PR is intentionally ugly. It duplicates all of the code in cli/js2/ into
cli/tsc/  ... because it's very important that we all understand that this code
is unnecessarily duplicated in our binary. I hope this ugliness provides the
motivation to clean it up.

The typescript git submodule is removed, because it's a very large repo and
contains all sorts of stuff we don't need. Instead the necessary files are
copied directly into the deno repo. Hence +200k lines.

COMPILER_SNAPSHOT.bin size
```
master         3448139
this branch    3320972
```

Fixes #6812

1 files changed, 25 insertions, 0 deletions

diff --git a/cli/dts/lib.deno.window.d.ts b/cli/dts/lib.deno.window.d.ts
new file mode 100644
index 000000000..61c5abf8a
--- /dev/null
+++ b/cli/dts/lib.deno.window.d.ts
@@ -0,0 +1,25 @@
+// Copyright 2018-2020 the Deno authors. All rights reserved. MIT license.
+
+/* eslint-disable @typescript-eslint/no-explicit-any */
+
+/// <reference no-default-lib="true" />
+/// <reference lib="deno.ns" />
+/// <reference lib="deno.shared_globals" />
+/// <reference lib="esnext" />
+
+declare interface Window extends EventTarget {
+  readonly window: Window & typeof globalThis;
+  readonly self: Window & typeof globalThis;
+  onload: ((this: Window, ev: Event) => any) | null;
+  onunload: ((this: Window, ev: Event) => any) | null;
+  close: () => void;
+  readonly closed: boolean;
+  Deno: typeof Deno;
+}
+
+declare const window: Window & typeof globalThis;
+declare const self: Window & typeof globalThis;
+declare const onload: ((this: Window, ev: Event) => any) | null;
+declare const onunload: ((this: Window, ev: Event) => any) | null;
+
+/* eslint-enable @typescript-eslint/no-explicit-any */