bitbake-dev: Refactor the environment variable handling.

Do not clear the environment when saving the environment to the data store.
Instead clear this once the cooker has forked. This ensures that the UI
operates in a filtered (but not empty) environment.

git-svn-id: https://svn.o-hand.com/repos/poky/trunk@5526 311d38ba-8fff-0310-9ca6-ca027cbcb966

bitbake-dev/lib/bb/cooker.py

@@ -907,6 +907,10 @@ class BBCooker:
 
     def serve(self):
 
+        # Empty the environment. The environment will be populated as
+        # necessary from the data store.
+        bb.utils.empty_environment()
+
         if self.configuration.profile:
             try:
                 import cProfile as profile