Bug 1330746 - Disable terminal-style output when running within emacs, r=qdot

MozReview-Commit-ID: CgjgL91alUa

--HG--
extra : rebase_source : ba00d397e310d1f3159ff2239ebc3c158184305c

python/mozbuild/mozbuild/mach_commands.py

@@ -210,6 +210,8 @@ class BuildOutputManager(LoggingMixin):
         # TODO convert terminal footer to config file setting.
         if not terminal or os.environ.get('MACH_NO_TERMINAL_FOOTER', None):
             return
+        if os.environ.get('INSIDE_EMACS', None):
+            return
 
         self.t = terminal
         self.footer = BuildProgressFooter(terminal, monitor)