Bug 1055596 - Make sure that stackwalk binary is installed when running web-platform-tests, r=jgriffin

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extra : rebase_source : efa57f0e306b4ff124faf1693bbaef89352969fe
Merging from default

changeset:   3089:8af374186284
tag:         tip
parent:      3087:1e523d7887dd
user:        James Graham <james@hoppipolla.co.uk>
date:        Thu Aug 21 23:38:19 2014 +0100
summary:     Bug 1055596 - Make sure that stackwalk binary is installed when running web-platform-tests, r=jgriffin

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branch : production