Test that safe saves are picked up by pub serve.
Test that safe saves are picked up by pub serve.

BUG=https://code.google.com/p/dart/issues/detail?id=21402
R=nweiz@google.com

Review URL: https://codereview.chromium.org//870703003

git-svn-id: a962b240025cf0577aa172e20f49ccb159ba6be1@43082 260f80e4-7a28-3924-810f-c04153c831b5

computmaxer/pub,dart-lang/pub,dart-lang/pub,cjkao/dart-pub,maxwellpeterson-wf/pub