hgweb: fix unbundle.

After the WSGI changes, even if a push over HTTP succeeds, apache
complains about "Premature end of script headers: hgwebdir.cgi" and
returns a "HTTP Error 500: Internal Server Error", making the local hg
abort.

The change to either of the files touched by this patch is enough to fix
this, but I think changing both is a more robust solution.

mercurial/hgweb/hgweb_mod.py

@@ -932,10 +932,11 b' class hgweb(object):'
 
                 try:
                     ret = self.repo.addchangegroup(fp, 'serve')
+                finally:
+                    val = sys.stdout.getvalue()
+                    sys.stdout = old_stdout
                     req.write('%d\n' % ret)
-                    req.write(sys.stdout.getvalue())
-                finally:
-                    sys.stdout = old_stdout
+                req.write(val)
             finally:
                 lock.release()
         finally:

mercurial/hgweb/wsgicgi.py

@@ -27,6 +27,7 b' def launch(application):'
 
     headers_set = []
     headers_sent = []
+    out = sys.stdout
 
     def write(data):
         if not headers_set:
@@ -35,13 +36,13 b' def launch(application):'
         elif not headers_sent:
              # Before the first output, send the stored headers
              status, response_headers = headers_sent[:] = headers_set
-             sys.stdout.write('Status: %s\r\n' % status)
+             out.write('Status: %s\r\n' % status)
              for header in response_headers:
-                 sys.stdout.write('%s: %s\r\n' % header)
-             sys.stdout.write('\r\n')
+                 out.write('%s: %s\r\n' % header)
+             out.write('\r\n')
 
-        sys.stdout.write(data)
-        sys.stdout.flush()
+        out.write(data)
+        out.flush()
 
     def start_response(status,response_headers,exc_info=None):
         if exc_info: