Merge changes from topic "remove-legacy-logger_entry-structs"

* changes:
  liblog: document the liblog<->logd protocol format
  liblog: remove unused parts of android_log_transport_context
  Remove old logger_entry_v* formats
  liblog: disable header_abi_checker
tree: 968820f4602236beea51ae159b15e00f8e45f7ca
  1. liblog/
  2. logcat/
  3. logd/
  4. logwrapper/