cooker: Ensure bbappend files are processed in a determistic order

index 68aa532..b0f4e4b 100644
@@ -1576,6 +1576,7 @@ class CookerExit(bb.event.Event):
 class CookerCollectFiles(object):
     def __init__(self, priorities):
         self.appendlist = {}
+        self.bbappends = []
         self.appliedappendlist = []
         self.bbfile_config_priorities = priorities
 

@@ -1670,6 +1671,7 @@ class CookerCollectFiles(object):
         # Build a list of .bbappend files for each .bb file
         for f in bbappend:
             base = os.path.basename(f).replace('.bbappend', '.bb')
+            self.bbappends.append((base, f))
             if not base in self.appendlist:
                self.appendlist[base] = []
             if f not in self.appendlist[base]:

@@ -1695,11 +1697,11 @@ class CookerCollectFiles(object):
         """
         filelist = []
         f = os.path.basename(fn)
-        for bbappend in self.appendlist:
+        for b in self.bbappends:
+            (bbappend, filename) = b
             if (bbappend == f) or ('%' in bbappend and bbappend.startswith(f[:bbappend.index('%')])):
                 self.appliedappendlist.append(bbappend)
-                for filename in self.appendlist[bbappend]:
-                    filelist.append(filename)
+                filelist.append(filename)
         return filelist
 
     def collection_priorities(self, pkgfns, d):

@@ -1719,10 +1721,10 @@ class CookerCollectFiles(object):
                 unmatched.add(regex)
 
         def findmatch(regex):
-            for bbfile in self.appendlist:
-                for append in self.appendlist[bbfile]:
-                    if regex.match(append):
-                        return True
+            for b in self.bbappends:
+                (bbfile, append) = b
+                if regex.match(append):
+                    return True
             return False
 
         for unmatch in unmatched.copy():