bitbake: toaster: add getMessage to MockEvent

The MockEvent needs to not only stand in for Toaster and Bitbake quick events,
it also needs to stand in for LogRecord, and for that it needs to provide
the new getMessage method.

[YOCTO #11440]

(Bitbake rev: d1ac359d460b1abe9815f323b3fd4cd0231cde6c)

Signed-off-by: David Reyna <David.Reyna@windriver.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>

bitbake/lib/bb/ui/buildinfohelper.py

@@ -858,6 +858,12 @@ class MockEvent(object):
         self.pathname = None
         self.lineno = None
 
+    def getMessage(self):
+        """
+        Simulate LogRecord message return
+        """
+        return self.msg
+
 
 class BuildInfoHelper(object):
     """ This class gathers the build information from the server and sends it