bitbake: hob & bitbake: append a value to a variable from hob throught bitbake

It was necessary to append ${TOPDIR}/recipes/images to BBFILES.
Implemented the mechanism to append a value to a variable: a command and
the method in cooker.

[YOCTO #4193]
(Bitbake rev: 4aedbee90bd92395c2460a68702e6ede00e256c9)

Signed-off-by: Cristiana Voicu <cristiana.voicu@intel.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>

bitbake/lib/bb/ui/crumbs/builder.py

@@ -440,6 +440,7 @@ class Builder(gtk.Window):
         self.handler.connect("recipe-populated",         self.handler_recipe_populated_cb)
         self.handler.connect("package-populated",        self.handler_package_populated_cb)
 
+        self.handler.append_to_bbfiles("${TOPDIR}/recipes/images/*.bb")
         self.initiate_new_build_async()
 
         signal.signal(signal.SIGINT, self.event_handle_SIGINT)

bitbake/lib/bb/ui/crumbs/hobeventhandler.py

@@ -471,9 +471,18 @@ class HobHandler(gobject.GObject):
 
     def set_var_in_file(self, var, val, default_file=None):
         self.runCommand(["enableDataTracking"])
-        self.server.runCommand(["setVarFile", var, val, default_file])
+        self.server.runCommand(["setVarFile", var, val, default_file, "set"])
         self.runCommand(["disableDataTracking"])
 
+    def append_var_in_file(self, var, val, default_file=None):
+        self.server.runCommand(["setVarFile", var, val, default_file, "append"])
+
+    def append_to_bbfiles(self, val):
+        bbfiles = self.runCommand(["getVariable", "BBFILES", "False"]) or ""
+        bbfiles = bbfiles.split()
+        if val not in bbfiles:
+            self.append_var_in_file("BBFILES", val, "local.conf")
+
     def get_parameters(self):
         # retrieve the parameters from bitbake
         params = {}