message: Increase AdbClient read timeout
  The previous value was not sufficient for Pixel 2 phones. One would have
  hoped that the newer phones are faster, but that does not seem to be the
  case here.
diff: @@ -46,7 +46,7 @@ using namespace std::chrono;
  namespace {
  -const seconds kReadTimeout(12);
  +const seconds kReadTimeout(20);
  const char *kOKAY = "OKAY";
  const char *kFAIL = "FAIL";
  const char *kDATA = "DATA";
  