DO NOT MERGE ANYWHERE Bring back support for legacy bt_config.xml

An earlier CL introducing backup support for bt_config.conf blew up
support for legacy file, making upgrading from L-based OS to M-based OS
lose its bluetooth config.

BUG=27824878

Change-Id: Ic23ef2a3559b04224278edffdc0e9380c2760638
1 file changed
tree: 8fceba191096ea49246a7d3a071147912a2edf90
  1. gki/
  2. system/
  3. Android.mk
  4. CleanSpec.mk
  5. MODULE_LICENSE_APACHE2
  6. NOTICE