Fix one dangling utf8 decode call needed for python 3.
Fix one dangling utf8 decode call needed for python 3.

With this change, the tests should run fine on Python3 on Macs.
Python2 should work fine as well :).

Bug: gyp:36
Change-Id: I044746d44143b2e461feb4e5685d8bef3d6bbd19
Reviewed-on: https://chromium-review.googlesource.com/c/1361812
Reviewed-by: Mark Mentovai <f1b5a91d4d6ad523f2610114591c007e75d15084@chromium.org>

chromium/gyp,turbulenz/gyp,turbulenz/gyp,turbulenz/gyp,msc-/gyp,msc-/gyp,msc-/gyp,chromium/gyp,msc-/gyp,msc-/gyp,turbulenz/gyp,chromium/gyp,chromium/gyp,chromium/gyp,turbulenz/gyp