Infra side changes to add a 32 bit Windows 7 bot.

masters/master.chromium.win/slaves.cfg

 # -*- python -*-
 # ex: set syntax=python:
 
 # Copyright (c) 2012 The Chromium Authors. All rights reserved.
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
 
 # See master.experimental/slaves.cfg for documentation.
 
 
@@ skipping 12 matching lines @@
   {
     'master': 'ChromiumWin',
     'hostname': 'vm809-m1',
     'builder': 'XP Tests (1)',
     'os': 'win',
     'version': 'xp',
     'bits': '32',
   },
   {
     'master': 'ChromiumWin',
+    'hostname': 'vm92-m1',
+    'builder': 'Win7 (32) Tests',
+    'os': 'win',
+    'version': 'win7',
+    'bits': '32',
+  },
+  {
+    'master': 'ChromiumWin',
     'hostname': 'vm805-m1',
     'builder': 'Vista Tests (1)',
     'os': 'win',
     'version': 'vista',
     'bits': '64',
   },
   {
     'master': 'ChromiumWin',
     'hostname': 'vm801-m1',
     'builder': 'Win7 Tests (1)',
@@ skipping 67 matching lines @@
   },
   {     
     'master': 'ChromiumWin',    
     'builder': 'Win8 GN (dbg)', 
     'hostname': 'vm876-m1',
     'os': 'win',        
     'version': 'win8',  
     'bits': '64',       
   },
 ]