The passive worker was being added to the session once per datatype. Fix it so it gets added only once so we dont do extra processing.
The passive worker was being added to the session once per datatype. Fix it so it gets added only once so we dont do extra processing.

BUG=80049
TEST=

Review URL: http://codereview.chromium.org/6880082

git-svn-id: de016e52bd170d2d4f2344f9bf92d50478b649e0@82411 0039d316-1c4b-4281-b951-d872f2087c98

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