Review Request: Switch user before downloading executors or setting up environment.

[Benjamin Hindman]

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This is an automatically generated e-mail. To reply, visit:
https://reviews.apache.org/r/5115/
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Review request for mesos, John Sirois and Vinod Kone.


Summary
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See summary.


Diffs
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  src/launcher/launcher.cpp 5c2c9e3 

Diff: https://reviews.apache.org/r/5115/diff


Testing
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make check


Thanks,

Benjamin