Example of how to interpose yourself in a message stream.

chrome/chrome.gyp

 # Copyright (c) 2011 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': {
     'chromium_code': 1,
 
     'variables': {
       'version_py_path': 'tools/build/version.py',
       'version_path': 'VERSION',
@@ skipping 831 matching lines @@
             'service/remoting/chromoting_host_manager.cc',
             'service/remoting/chromoting_host_manager.h',
           ],
         }],
       ],
     },
     {
       'target_name': 'ipclist',
       'type': 'executable',
       'dependencies': [
-         'chrome',
-         'chrome_resources',
-         'chrome_strings',
-         'test_support_common',
-         'test_support_ui',
+          'test_support_common',

[jam, 2011/04/28 23:43:46]

nit: spacing is off

          '../skia/skia.gyp:skia',
-         '../testing/gtest.gyp:gtest',
-         '../third_party/libxslt/libxslt.gyp:libxslt',
-         '../third_party/npapi/npapi.gyp:npapi',
       ],
       'include_dirs': [
          '..',
       ],
       'sources': [
         'tools/ipclist/all_messages.h',
         'tools/ipclist/ipclist.cc',
       ],
     },
+    {
+      'target_name': 'ipcfuzz',
+      'type': 'loadable_module',
+      'include_dirs': [
+         '..',
+      ],
+      'dependencies': [
+         'test_support_common',
+         '../skia/skia.gyp:skia',
+      ],
+      'sources': [
+        'tools/ipclist/all_messages.h',
+        'tools/ipclist/ipcfuzz.cc',
+      ],
+    },
   ],
   'conditions': [
     ['OS=="mac"',
       { 'targets': [
         {
           'target_name': 'helper_app',
           'type': 'executable',
           'product_name': '<(mac_product_name) Helper',
           'mac_bundle': 1,
           'dependencies': [
@@ skipping 725 matching lines @@
       }],  # targets
     }],  # OS=="linux" or OS=="freebsd" or OS=="openbsd" or OS=="solaris"
   ],  # 'conditions'
 }
 
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