perf: Don't persist the perf profile across a reboot

 * Always initialize with the default performance profile.
 * There are a lot of reasons for this, but mostly because
   users are stumbling into the setting and ending up with a
   slow system because they enabled powersave mode.

Change-Id: Icd0a1ddcc41700eb29a126bda1eb67a26fc2d5dd
perf: Send a boost hint when a key on the navbar is pressed

 * A lot of stuff happens, especially when invoking recents.
 * Get ahead of the storm by sending a boost hint before
   kicking off the animations.

Change-Id: I0cecd0c58f8bc8479ea44f63af796500d7b9d7d2