Exit the installer gracefully if the processor doesn't support SSE2.

chrome/chrome_installer.gypi

 # 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.
 
 {
   'variables': {
     'lastchange_path': '../build/util/LASTCHANGE',
     'libpeer_target_type%': 'static_library',
     # 'branding_dir' is set in the 'conditions' section at the bottom.
   },
@@ skipping 275 matching lines @@
             'installer/setup/setup_constants.cc',
             'installer/setup/setup_constants.h',
             'installer/setup/setup_exe_version.rc.version',
             'installer/setup/setup_resource.h',
             'installer/setup/setup_util.cc',
             'installer/setup/setup_util.h',
             'installer/setup/uninstall.cc',
             'installer/setup/uninstall.h',
           ],
           'msvs_settings': {
+            'VCCLCompilerTool': {
+              'EnableEnhancedInstructionSet': '4',  # NoExtensions
+            },
             'VCLinkerTool': {
               'SubSystem': '2',     # Set /SUBSYSTEM:WINDOWS
             },
             'VCManifestTool': {
               'AdditionalManifestFiles': [
                 '$(ProjectDir)\\installer\\setup\\setup.exe.manifest',
               ],
             },
           },
           # TODO(jschuh): crbug.com/167187 fix size_t to int truncations.
@@ skipping 817 matching lines @@
          'branding_dir_100': 'app/theme/default_100_percent/google_chrome',
       },
     }, { # else branding!="Chrome"
       'variables': {
          'branding_dir': 'app/theme/chromium',
          'branding_dir_100': 'app/theme/default_100_percent/chromium',
       },
     }],
   ],
 }