Upcoming changes to Chromium OS change how accelerometers are presented.

Currently both base and lid accelerometers are presented as a single iio_device. AccelerometerReader would read this file system to get the needed information.

Now they are being separated into different iio_devices. There have been other changes to the underlying file system that needs to be addressed for correct initialization.

This change update AccelerometerReader to handle this new format. While preserving the legacy path for devices on older kernels.

TEST=Manual testing on devices. This was loaded on a device representing both kernel versions.
BUG=515949, chrome-os-partner:40177, 431391

Review URL: https://codereview.chromium.org/1306453003

Cr-Commit-Position: refs/heads/master@{#346148}
6 files changed