Malloc issue with iOS 7.1

[gavin-black]

Seeing the following:
*** set a breakpoint in malloc_error_break to debug
SFUnitTest(58515,0x5c2b1a8) malloc: *** error for object 0x8e94490: pointer being freed was not allocated
*** set a breakpoint in malloc_error_break to debug

when running test cases with iOS 7+. It seems to happen when things are being cleaned up after running, and is not stopping execution. It does not appear on iOS 6.1 simulators, but does on actual devices.