Legacy FM stream support

Change-Id: I7fb18d69d27e5bcc7c590a8b4c019a107d280a28
Use RGB565 surface for wallpaper

Change-Id: I7db145882e7f84de5f0bd5e3991e96f929cb498c
Prefer 16bpp formats for opaque bitmaps

Change-Id: If9cf89d257b962d3c33ff4c1e5e29ad017ef092d