cleanup top level completion tests

BUG=
R=scheglov@google.com

Review URL: https://codereview.chromium.org//457093002

git-svn-id: https://dart.googlecode.com/svn/branches/bleeding_edge@39067 260f80e4-7a28-3924-810f-c04153c831b5
restore missing import

BUG=
R=brianwilkerson@google.com, scheglov@google.com

Review URL: https://codereview.chromium.org//457043004

git-svn-id: https://dart.googlecode.com/svn/branches/bleeding_edge@39068 260f80e4-7a28-3924-810f-c04153c831b5
local code completion suggestions

BUG=
R=scheglov@google.com

Review URL: https://codereview.chromium.org//454403003

git-svn-id: https://dart.googlecode.com/svn/branches/bleeding_edge@39069 260f80e4-7a28-3924-810f-c04153c831b5