feat: Add content script world isolation (#17032)

* Execute content script in isolated world

* Inject script into newly created extension worlds

* Create new content_script_bundle for extension scripts

* Initialize chrome API in content script bundle

* Define Chrome extension isolated world ID range

1 << 20 was chosen as it provides a sufficiently large range of IDs for extensions, but also provides a large enough buffer for any user worlds in [1000, 1 << 20).

Ultimately this range can be changed if any user application raises it as an issue.

* Insert content script CSS into document

This now avoids a script wrapper to inject the style sheet. This closely matches the code used by chromium in `ScriptInjection::InjectCss`.

* Pass extension ID to isolated world via v8 private

lib/content_script/init.js

@@ -0,0 +1,35 @@
+'use strict'
+
+/* global nodeProcess, isolatedWorld, worldId */
+
+const { EventEmitter } = require('events')
+
+process.atomBinding = require('@electron/internal/common/atom-binding-setup').atomBindingSetup(nodeProcess.binding, 'renderer')
+
+const v8Util = process.atomBinding('v8_util')
+// The `lib/renderer/ipc-renderer-internal.js` module looks for the ipc object in the
+// "ipc-internal" hidden value
+v8Util.setHiddenValue(global, 'ipc-internal', new EventEmitter())
+// The process object created by browserify is not an event emitter, fix it so
+// the API is more compatible with non-sandboxed renderers.
+for (const prop of Object.keys(EventEmitter.prototype)) {
+  if (process.hasOwnProperty(prop)) {
+    delete process[prop]
+  }
+}
+Object.setPrototypeOf(process, EventEmitter.prototype)
+
+const isolatedWorldArgs = v8Util.getHiddenValue(isolatedWorld, 'isolated-world-args')
+
+if (isolatedWorldArgs) {
+  const { ipcRendererInternal, guestInstanceId, isHiddenPage, openerId, usesNativeWindowOpen } = isolatedWorldArgs
+  const { windowSetup } = require('@electron/internal/renderer/window-setup')
+  windowSetup(ipcRendererInternal, guestInstanceId, openerId, isHiddenPage, usesNativeWindowOpen)
+}
+
+const extensionId = v8Util.getHiddenValue(isolatedWorld, `extension-${worldId}`)
+
+if (extensionId) {
+  const chromeAPI = require('@electron/internal/renderer/chrome-api')
+  chromeAPI.injectTo(extensionId, false, window)
+}