Pager extension: switch it off if --debugger is set

The pager is preventing the debugger prompt and much of the
debugger output to be refreshed. Moreover the pager does not
make sense when debugging line by line.

(This supersedes the similar ui.debugflag patch. Disabling
the pager for debug output doesn't make that much sense,
as this is actually when the pager might be useful.)

hgext/pager.py

@@ -1,35 +1,35
 # pager.py - display output using a pager
 #
 # Copyright 2008 David Soria Parra <[e-mail]>
 #
 # This software may be used and distributed according to the terms
 # of the GNU General Public License, incorporated herein by reference.
 #
 # To load the extension, add it to your .hgrc file:
 #
 #   [extension]
 #   hgext.pager =
 #
 # To set the pager that should be used, set the application variable:
 #
 #   [pager]
 #   pager = LESS='FSRX' less
 #
 # If no pager is set, the pager extensions uses the environment
 # variable $PAGER. If neither pager.pager, nor $PAGER is set, no pager
 # is used.
 #
 # If you notice "BROKEN PIPE" error messages, you can disable them
 # by setting:
 #
 #   [pager]
 #   quiet = True
 
 import sys, os, signal
 
 def uisetup(ui):
     p = ui.config("pager", "pager", os.environ.get("PAGER"))
-    if p and sys.stdout.isatty() and not ui.debugflag:
+    if p and sys.stdout.isatty() and '--debugger' not in sys.argv:
         if ui.configbool('pager', 'quiet'):
             signal.signal(signal.SIGPIPE, signal.SIG_DFL)
         sys.stderr = sys.stdout = os.popen(p, "wb")