am 51710a73: am 82319a98: am 468a0417: am c95714b3: am ec8c2ac9: Merge "Calculate available background threads for AttachmentService correctly." into ub-gmail-ur14-dev

* commit '51710a73cd1754a9594a8794fa658d98e6ee326a':
  Calculate available background threads for AttachmentService correctly.