Fix overflow testing in sbrk. am: 1944780b62 am: 3a5ebf3154  -s ours am: d95336ac42 am: 0993319651 am: 0ae30d9af8 am: 83b0671a33 am: 10a48fb557
am: fd84d78b1e

* commit 'fd84d78b1e0840905b80a4c4072db27b5e3aa2c9':
  Fix overflow testing in sbrk.

Change-Id: I8bf29354a9a631ad7c33a1eab3f66124546b7331