Unmount all asec apps before encrypting

Now that forward locked apps are stored on /data as asec image files
that are mounted, they need to be unmounted before /data can be unmounted
so it can be encrypted.

Change-Id: I7c87deb52aaed21c8ad8ce8aceb7c15c2338620a
diff --git a/VolumeManager.h b/VolumeManager.h
index 3802503..4399b76 100644
--- a/VolumeManager.h
+++ b/VolumeManager.h
@@ -136,6 +136,7 @@
     Volume *lookupVolume(const char *label);
     int getNumDirectVolumes(void);
     int getDirectVolumeList(struct volume_info *vol_list);
+    int unmountAllAsecsInDir(const char *directory);
 
 private:
     VolumeManager();
@@ -150,6 +151,7 @@
     int vold_disableVol(const char *label);
     int vold_getNumDirectVolumes(void);
     int vold_getDirectVolumeList(struct volume_info *v);
+    int vold_unmountAllAsecs(void);
 #ifdef __cplusplus
 }
 #endif