Close servers for bin directories when precompiling executables.
Close servers for bin directories when precompiling executables.

R=rnystrom@google.com
BUG=20482

Review URL: https://codereview.chromium.org//491103002

git-svn-id: a962b240025cf0577aa172e20f49ccb159ba6be1@39431 260f80e4-7a28-3924-810f-c04153c831b5

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