bitbake: lib/bb/event: refactor printing events

We really ought to have just one place where the string representation
of these events is produced. This doesn't take any real control away
from the UI - if an alternative representation is desired, that can
still be made.

(Bitbake rev: cb15db2a799be6d8eab9a2a43a9a573f89229cff)

Signed-off-by: Paul Eggleton <paul.eggleton@linux.intel.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>

bitbake/lib/bb/command.py

@@ -50,6 +50,8 @@ class CommandFailed(CommandExit):
     def __init__(self, message):
         self.error = message
         CommandExit.__init__(self, 1)
+    def __str__(self):
+        return "Command execution failed: %s" % self.error
 
 class CommandError(Exception):
     pass