fix two warnings
Merge pull request #108 from dart-gde/warnings

fix two warnings
Add initial version of chrome.devtools.inspectedWindow APIs
Revert harness_extension.html
Added tests for devtools.dart.

To run tests, goto any url, then hit CTRL-SHIFT-I to
open the Developer Tools. There should be a new panel, 'harness_devtools'.
Select it and the test should run.

Tested on Dartium and Chrome.
Merge branch 'devtools' of https://github.com/DrMarcII/chrome.dart into devtools