Changes to the api doc app to remove indentation spaces

Review URL: https://chromiumcodereview.appspot.com//12330121
Fix CSS bug
Update AST to take advantage of the new dependency JSON.  This simplifies some logic and lets more bindings be one way.
Merge branch 'master' of https://github.com/dart-lang/dart-api-app into components
fixed minor but if typing complete library e.g., dart:io and pressing enter