chromeos-google-touch: make get_active_firmware_version more robust

If the touch updater tries to detect the firmware version during RWSIG
jump, it will get an empty string, which makes the touch updater to
think the firmware is corrupted on the touchpad and tries to reflash it.
We should recheck for firmware version when the returned firmware
version is empty to avoid this issue.

Signed-off-by: Wei-Ning Huang <wnhuang@google.com>

BUG=b:64702500
TEST=manually

Change-Id: I948e024fcad1ebc94ce98d1130e705530615175d
Reviewed-on: https://chromium-review.googlesource.com/614823
Commit-Ready: Wei-Ning Huang <wnhuang@chromium.org>
Tested-by: Wei-Ning Huang <wnhuang@chromium.org>
Reviewed-by: Wei-Ning Huang <wnhuang@chromium.org>
(cherry picked from commit 6a4496ab82f08c50fc1dbe54f88b8b94a8f30bd6)
Reviewed-on: https://chromium-review.googlesource.com/618184
Commit-Queue: Wei-Ning Huang <wnhuang@chromium.org>
1 file changed
tree: b44e71622421f3a589cc66e491e3bec8c28be5bc
  1. host_scripts/
  2. policies/
  3. scripts/
  4. LICENSE
  5. OWNERS
  6. README