Avoid timeouts in stack_trace's chain_test.

R=rnystrom@google.com
BUG=18142

Review URL: https://codereview.chromium.org//232783008

git-svn-id: https://dart.googlecode.com/svn/branches/bleeding_edge/dart/pkg/stack_trace@34940 260f80e4-7a28-3924-810f-c04153c831b5
1 file changed
tree: f1e563a93e8fe1340ce9e47e213d9be66bca4cca
  1. pkgs/