tree f1641627b56893148de037fe93782e339db3e892
parent 9ab6af5a61e86716a1628713c7ad6dc239f47325
author Tao Bao <tbao@google.com> 1478242321 -0700
committer Tao Bao <tbao@google.com> 1479447032 -0800

DO NOT MERGE updater: Add "write_value()" function.

write_value(value, filename) writes 'value' to 'filename'. It can be
used to tune device settings when applying an OTA package. For example,
write_value("960000", "/sys/devices/system/cpu/cpu0/cpufreq/scaling_max_freq").

Bug: 32463933
Test: recovery_component_test passes.
Test: Apply an OTA package that contains a call to write_value(), and
      check the result.

Change-Id: Ib009ecb8a45a94353f10c59e2383fe1f49796e35
(cherry picked from commit d0f3088aa95e255b39ed4b83da6b08866c2c3e0c)