Merge "Report errno more often in fastboot." am: 8c5384e50b am: 272b2694cd
am: 7f80f04a2c

* commit '7f80f04a2ce9b3fa28be456c89c50a5fd2b5923d':
  Report errno more often in fastboot.

Change-Id: Id6c53aa1a2d34fcb4c4f49fac34fc83209ac1703