Revert "Build Observatory with runtime"

runtime/bin/vmservice/observatory/HACKING.txt

+Dart Observatory Developer Guide
+---
+
+Assumptions:
+You are running pub from the latest dev channel release of Dart Editor.
+
+During development you do not need to run dart2js or rebuild the VM (unless
+you are also making changes to the backend). While you're working on your
+feature follow the steps:
+
+1. Open runtime/bin/vmservice/observatory in the Dart Editor
+2. Run pub upgrade
+3. Run dart --observe script.dart
+4. Run index.html in Dartium
+
+At this point you should see the initial Observatory UI and that
+it is communicating with the VM you launched in step 3.
+
+Continue to develop and iterate until you're ready to upload your change
+for review. Upload your change and get an LGTM.
+
+5. Run pub build
+6. Run ./deploy.sh
+
+Note: If you run pub from within the editor you need to make sure that it runs
+in release mode (--mode=release), i.e., output is minified and does not include
+any .dart source files.
+
+At this point you should rebuild your VM and:
+
+7. Launch dart --observe script.dart
+
+In a non-Dart enabled browser navigate to localhost:8181 and ensure
+that your feature works after being compiled to JavaScript.
+
+8. Ensure the vm, standalone, and observatory unit tests still pass:
+python tools/test.py --mode=debug --arch=ia32 --compiler=none --runtime=vm vm/cc standalone/vmservice vmservice
+
+9. Commit your change