adb calls bugreportz to generate a bugreport; initially, bugreportz
would only report the final status of the operation (OK or FAIL), but
now it sends intermediate PROGRESS lines reporting its progress (in the
form of current/max).
Similarly, the initial implementation of 'adb bugreport <zip_file>'
would print an initial 'please wait' message and wait for the full
stdout before parsing the result, but now it uses a new callback class
to handle the stdout as it is generated by bugreportz.
BUG: 28609499
Change-Id: I6644fc39a686279e1635f946a47f3847b547d1c1
bugreport() will be soon refactored to track progress, which will
require more comprehensive unit tests.
As such, it's better to move it to its own files, which in turn also
requires moving send_shell_command() and usage() to commandline.h.
Fixes: 30100363
Bug: 30268737
Change-Id: I3cdf114a0b5547293320042ff0749a60886440b0
