Fix overflow testing in sbrk. am: 1944780b am: 3a5ebf31 -s ours am: d95336ac am: 09933196 am: 0ae30d9a am: 83b0671a am: 10a48fb5 * commit '10a48fb5': Fix overflow testing in sbrk. Change-Id: Ie5de1ba25e3a769ff57bd9280ae4d4d9625fe4ee