clean up reboot to main system and remove old useless variables

Change-Id: Idf8cda0639e3fa5e6073b196a85899c57ca18e9b
Signed-off-by: Willi Ye <williye97@gmail.com>

Conflicts:
	recovery.c
Don't return immediately from reboot commands.

The reboot commands return too fast, interfering with testing.
Add a pause(), which will allow the device time to complete the
reboot.

Change-Id: Ie9cc6eea67b7ff662ec71ea2329cbb94f8d55404
Bug: 11369303
Enable incremental builder to find files that moved, and
try to process them via patch + rename, instead of
delete + add.

b/11437930

Change-Id: I984349fbc9a8dac4379e00c0d66fc7d22c4eb834
Support recoveries without CONFIG_EXT4_FS_XATTR

If for some reason the recovery's kernel can't be replaced and has
no support for xattrs, use this. Chances are the system will break
unless you know what you're doing and compensate on the Android side

Change-Id: I09ff2cbd0ae68ec4f4b2a2e26acb6b0bc8b3569a
Remove redundant variable definition

The same Volume variable is defined with two names in the same scope.
Merge the names and remove one of the definitions.

Change-Id: I021697b42791bc6323c5fa0d9704d27ecfe2c8c1
(cherry picked from commit d98fabe2aa8df0e421a69130c1d787705209682d)
Do data/media checks first in format_device()

Wait to define a Volume variable until data/media checks are done
in case the Volume definition is unnecessary.

Change-Id: I6912b1b2a473ea8737ea3e415e9a0172bb35eff1
(cherry picked from commit dd812777f0bbb7075da8c3da6a18612fa90e100e)
recovery: Add support for performance control

 * Recovery will now set "recovery.perf.mode" to 1 before a
   backup/restore operation begins, and will set it back to 0
   when the operation is complete. It will also do this during
   package installations.
 * This allows devices to boot into recovery in a low-power mode,
   and bring up more cores and adjust other settings. Pigz is
   multithreaded, and enabling all cores vastly improves performance of
   compressed backups.
 * Device maintainers who wish to use this should configure their
   init.recovery script to trigger off of this property.

Change-Id: I174e45215ad1cd34a34b1af4486a64fb6e54134b
Define paths for recovery settings files in a separate header

Also, use get_primary_storage_path() to define the locations of .no_confirm,
.many_confirm, and .hidenandroidprogress instead of hard-coding /sdcard/.

Change-Id: I50442a226af1d102786c833c0b53c25bf63c67a6
(cherry picked from commit bd0fe453f6ca242f0ed868b4c0934af29d499bba)