[Author: dmaclach]
[Author: dmaclach]

Fix up another case of bad format string handling by various versions of Xcode.

R=thomasvl
DELTA=15  (15 added, 0 deleted, 0 changed)

jonreid/google-toolbox-for-mac,jonreid/google-toolbox-for-mac,jonreid/google-toolbox-for-mac