Check all lseek calls succeed.

Also add missing TEMP_FAILURE_RETRYs on read, write, and lseek.

Bug: http://b/20625546
Change-Id: I03b198e11c1921b35518ee2dd005a7cfcf4fd94b
(cherry picked from commit 7bad7c4646ee8fd8d6e6ed0ffd3ddbb0c1b41a2f)
14 files changed