Update backuptool.sh to correctly process force_backuptool flag/file.

This is regarding the following patch:
https://github.com/CyanogenMod/android_vendor_cyanogen/commit/5cdb4ec653b06721dcc6f0b486943d62a1a4c8c2

The patch which was to allow custom_backup_list.txt to be maintained while flashing via ROMManager
WHILE the flag/file force_backuptool is set/present still has issues.  There are 2 reasons for this.

1) The flag is only checked during the first pass (backuptool.sh backup), as once /etc/force_backuptool
   is known to exist, all files are moved to /tmp/backupdir as designated, but when the script is
   ran again once /system has been wiped and updated, the file /etc/force_backuptool no longer exists
   as it was moved to /tmp/backupdir/force_backuptool, so the script fails as it is not checking that
   location.

2) When the backuptool.sh script is called, the above function (checking for force_backuptool) is called
   *before* the /system partition is mounted.  This therefor ignores the file regardless of whether it
   exists or not.  This is caused by check_installscript being called at the wrong point of the script.

There are therefor 2(two) main changes to this script to allow the force_backuptool override to work.
The first being within the main function of check_installscript, and the second being the location of
where check_installscript is called (ie, I moved it to below check_prereq call in the case statement,
as mounting is called before the check_prereq function checks if the ROM version is the same).

This affects *all* devices.

Change-Id: Ia7438f396eaa91b0723e56bb32ce98725e2b2025

1 files changed, 13 insertions, 5 deletions

diff --git a/prebuilt/common/bin/backuptool.sh b/prebuilt/common/bin/backuptool.sh
index dc4590a..39666ce 100755
--- a/prebuilt/common/bin/backuptool.sh
+++ b/prebuilt/common/bin/backuptool.sh
@@ -18,10 +18,18 @@ check_prereq() {
 }
 
 check_installscript() {
-   if [ -f "/tmp/.installscript" -a ! -f "$S/etc/force_backuptool" ];
+   if [ -f "/tmp/.installscript" ] && [ $PROCEED -ne 0 ];
    then
-      echo "/tmp/.installscript found. Skipping backuptool."
-      PROCEED=0;
+      # We have an install script, and ROM versions match!
+      # We now need to check and see if we have force_backup
+      # in either /etc or /tmp/backupdir 
+      if [ -f "$S/etc/force_backuptool" ] || [ -f "$C/force_backuptool" ];
+      then
+         echo "force_backuptool file found, Forcing backuptool."
+      else
+         echo "/tmp/.installscript found. Skipping backuptool."
+         PROCEED=0;
+      fi
    fi
 }
 
@@ -132,12 +140,11 @@ restore_file() {
    fi
 }
 
-check_installscript;
-
 case "$1" in
    backup)
       mount $S
       check_prereq;
+      check_installscript;
       if [ $PROCEED -ne 0 ];
       then
          rm -rf $C
@@ -152,6 +159,7 @@ case "$1" in
    ;;
    restore)
       check_prereq;
+      check_installscript;
       if [ $PROCEED -ne 0 ];
       then
          for file_list in get_files get_custom_files; do