am 285bb8dd: am b9184809: Merge changes from topic \'gdbclient.py\'

* commit '285bb8ddef8f8b73a9a80ee5d3bd7a3ae68bc60b':
  Add gdbrunner package for shared functionality.
  Add get_props to adb.py's AndroidDevice.
  Add remount to adb.py's AndroidDevice.
  Add shell_popen method to adb.py.
  Add helper functions for `adb -e/-d` to adb.py.