[Android] [PATCH] Add support for multiple video instances.

[Thomas Guillem]

You should do 2 commits, one that touch
include/vlc/libvlc_media_player.h lib/media_player.c and src/libvlc.c.
This commit should be about adding libvlc_media_player_set_androidobject
into libvlc. The others commits should touch modules.

The name "Add support for multiple video instances" is not good, vlc is
not only about android, and support multiple video instance for other
platforms since a long time.

At the end, in src/libvlc.c
why drawable-vlcobject and not drawable-androidobject ?

You don't have to specify again  struct android_surf_value_t in vlc.
You can do: typedef struct android_surf_value_t android_surf_value_t;
vlc shouldn't have access to android_surf_value_t members.

Some comments don't match the function name (surfacevalue vs
androidobject)