logd: in nonblocking read, sched_yield() synchronization

- sched_yield and lock synchronization in reader thread
  startup to give writer thread a chance to catch up

(cherry picked from commit f669acb01880216b6c1d29fc226f2c3ec3a6368a)

Bug: 17512203
Change-Id: I43cf0b4e2829b22b3ab4e537fa95ce13c76a869c
1 file changed
tree: 0999370b7eb5c3e820f270d198174f5b87464fd3
  1. liblog/
  2. logcat/
  3. logd/
  4. logwrapper/