Step 1 in getting rid of duplicate warning in make build.

webkit/tools/npapi_layout_test_plugin/npapi_layout_test_plugin.gypi

 # Copyright (c) 2010 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.
 
 {
   'targets': [
     {
       'target_name': 'npapi_layout_test_plugin',
       'type': 'loadable_module',
       'variables': {
@@ skipping 71 matching lines @@
               '$(SDKROOT)/System/Library/Frameworks/Carbon.framework',
             ],
           },
         }],
         ['(OS=="linux" or OS=="freebsd" or OS=="openbsd" or OS=="solaris") and (target_arch=="x64" or target_arch=="arm")', {
           # Shared libraries need -fPIC on x86-64
           'cflags': ['-fPIC']
         }],
       ],
     },
+    {
+      'target_name': 'copy_npapi_layout_test_plugin',
+      'type': 'none',
+      'dependencies': [
+        'npapi_layout_test_plugin',
+      ],
+      'conditions': [
+        ['OS=="win"', {
+          'copies': [
+            {
+              'destination': '<(PRODUCT_DIR)/plugins',
+              'files': ['<(PRODUCT_DIR)/npapi_layout_test_plugin.dll'],
+            },
+          ],
+        }],
+        ['OS=="mac"', {
+          'copies': [
+            {
+              'destination': '<(PRODUCT_DIR)/TestShell.app/Contents/PlugIns/',
+              'files': ['<(PRODUCT_DIR)/TestNetscapePlugIn.plugin/'],
+            },
+          ]
+        }],
+        ['OS=="linux" or OS=="freebsd" or OS=="openbsd" or OS=="solaris"', {
+          'copies': [
+            {
+              'destination': '<(PRODUCT_DIR)/plugins',
+              'files': ['<(PRODUCT_DIR)/libnpapi_layout_test_plugin.so'],
+            },
+          ],
+        }],
+      ],
+    },
   ],
 }
 
 # Local Variables:
 # tab-width:2
 # indent-tabs-mode:nil
 # End:
 # vim: set expandtab tabstop=2 shiftwidth=2: