Ban cross origin WebSocket connections to the service protocol

runtime/observatory/HACKING.md

 # Hacking Observatory
 
 These instructions will guide you through the Observatory development and
 testing workflow.
 
 ## SDK Setup & Build
 Getting ready to start.
 
 Before you start to hack on Observatory, follow the [instructions][build_sdk] to
 have a working environment in which you are able to build and test the Dart SDK.
@@ skipping 51 matching lines @@
 main() {
   bool tick = true;
   new Timer.periodic(const Duration(seconds: 1), (Timer t) {
     print(tick ? 'tick' : 'tock');
     tick = !tick;
   });
 }
 ```
 Start the script:
 ```
-$ dart --observe clock.dart
+$ dart --disable-service-origin-check --observe clock.dart
 ```
 
 ## Code Reviews
 The development workflow of Dart (and Observatory) is based on code reviews.
 
 Follow the code review [instructions][code_review] to be able to successfully
 submit your code.
 
 The main reviewers for Observatory related CLs are:
   - turnidge
@@ skipping 101 matching lines @@
 ## Run your tests
 See: __Run existing tests__
 
 [build_sdk]: https://github.com/dart-lang/sdk/wiki/Building "Building the Dart SDK"
 [download_dartium]: https://www.dartlang.org/tools/dartium/ "Download Dartium"
 [build_dartium]: https://github.com/dart-lang/sdk/wiki/Building-Dartium "Build Dartium"
 [open_observatory]: http://localhost:8080/ "Open Observatory"
 [observatory_get_started]: https://dart-lang.github.io/observatory/get-started.html "Observatory get started"
 [code_review]: https://github.com/dart-lang/sdk/wiki/Code-review-workflow-with-GitHub-and-reitveld "Code Review"
 [test_library]: https://pub.dartlang.org/packages/test "Test Library"