Retry: Bug 1020158 - Send IAC message to start the population process

https://bugzilla.mozilla.org/show_bug.cgi?id=1020158

Retrying this to see what gaia-try does.

New PR on my personal travis: https://travis-ci.org/KevinGrandon/gaia/builds/27976205

On try-proper with the gecko fix from bug 1026737 here: https://tbpl.mozilla.org/?tree=Try&rev=f02fcef6012d

First gaia-try, has failures: https://tbpl.mozilla.org/?tree=Gaia-Try&rev=cc4afdcf78f382ab7dafe49b1b4de2ad4fadfc69

Second gaia-try, with sleep: https://tbpl.mozilla.org/?tree=Gaia-Try&rev=84ee855533782164606a16e1fb6c30bbfb7827bc

Third gaia-try, with condition: https://tbpl.mozilla.org/?tree=Gaia-Try&rev=5e0d3e8644c88e04dec92ecf2dc358075059e219

With test disabled: https://tbpl.mozilla.org/?tree=Gaia-Try&rev=87533f6246fd4dacfa2b5f6d91460bd1ffd03822