[MERGE] harmonize run_bzr_subprocess with run_bzr

[John Arbash Meinel]

John Arbash Meinel has voted tweak.
Status is now: Conditionally approved
Comment:
+            symbol_versioning.warn(zero_nineteen %
+                                   "passing varargs to run_bzr",
+                                   DeprecationWarning, stacklevel=3)

This should probably be complaining about 'run_bzr_subprocess', not 
'run_bzr'.

-        err = self.run_bzr_subprocess('merge', '--merge-type', 'magic 
merge',
+        err = self.run_bzr_subprocess('merge --merge-type magic\ 
merge',
                                        retcode=3)[1]
^- This is one of those cases where using the list form is a lot more 
obvious.
Also, you happened to get lucky that python doesn't have an escape for ' 
' so it treats '\ ' as r'\ '. It really should have been written '\\ '. 
(or including the 'r' variant).

Otherwise, I think run_bzr_subprocess should be updated, and you did 
that correctly.

For details, see: 
http://bundlebuggy.aaronbentley.com/request/%3C46B8B04E.3060300%40utoronto.ca%3E