Don't delete old version before new version is downloaded.

R=ricow@google.com

Review URL: https://codereview.chromium.org//692333008

git-svn-id: https://dart.googlecode.com/svn/branches/bleeding_edge@41632 260f80e4-7a28-3924-810f-c04153c831b5
Refactor browser test enqueuing in test scripts.

R=ricow@google.com

Review URL: https://codereview.chromium.org//700753004

git-svn-id: https://dart.googlecode.com/svn/branches/bleeding_edge@41633 260f80e4-7a28-3924-810f-c04153c831b5
Deferred hunks had a `.` too much in their file names.

R=floitsch@google.com

Review URL: https://codereview.chromium.org//639333002

git-svn-id: https://dart.googlecode.com/svn/branches/bleeding_edge@41634 260f80e4-7a28-3924-810f-c04153c831b5
Refactor test scripts browser multitest loop.

BUG=
R=ricow@google.com

Review URL: https://codereview.chromium.org//688323006

git-svn-id: https://dart.googlecode.com/svn/branches/bleeding_edge@41635 260f80e4-7a28-3924-810f-c04153c831b5