SurfaceFlinger: Support get/set ActiveConfigs

This includes the following two changes squashed into one and
retaining the change I182f41edbaf9226fc62d6d17ee964998cd9f21f7

sf: Fixes for resolution change in SurfaceFlinger

1. Use active config from HWC when querying display attributes

   When we query the display attributes we should use the active
   config as reported by HWC in cases where HWC version is 1.4.
   In all other cases we should revert to the default config,
   config 0, as the active config.

2. Set/update the display config if HWC config change was successful

   The new config should only be applied if HWC succeeded in changing
   the active config. This would otherwise cause failure or undefined
   behavior if the client sets an invalid/unsupported display config.

3. Set the active config at display creation time

   When a new display device is added update the active config by
   querying HWC.

   Change-Id: I182f41edbaf9226fc62d6d17ee964998cd9f21f7

sf: Initialize active config for non-virtual displays at boot time

When a non-virtual display device is added at boot time, update the
active config by querying HWC otherwise the default config (config 0)
will be used.

    Change-Id: I90f42fa1d20ed6176c4be464a10ae69a2f6a6d55

Change-Id: I182f41edbaf9226fc62d6d17ee964998cd9f21f7