Added a changelog to unittest
Deprecated a number of methods made extraneous by zone change
Fixed related issues in html and html tests

BUG= https://code.google.com/p/dart/issues/detail?id=13277
BUG= https://code.google.com/p/dart/issues/detail?id=16541
R=sigmund@google.com

Review URL: https://codereview.chromium.org//133313004

git-svn-id: https://dart.googlecode.com/svn/branches/bleeding_edge/dart/pkg/unittest@32400 260f80e4-7a28-3924-810f-c04153c831b5