Remove WEBKIT_DLL and replace it with COMPONENT_BUILD

Source/modules/modules.gyp

 #
 # Copyright (C) 2013 Google Inc. All rights reserved.
 #
 # Redistribution and use in source and binary forms, with or without
 # modification, are permitted provided that the following conditions are
 # met:
 #
 #     * Redistributions of source code must retain the above copyright
 # notice, this list of conditions and the following disclaimer.
 #     * Redistributions in binary form must reproduce the above
@@ skipping 23 matching lines @@
   ],
   'targets': [{
     'target_name': 'modules',
     'type': 'static_library',
     'dependencies': [
       '<(DEPTH)/third_party/zlib/zlib.gyp:zlib',
       '../config.gyp:config',
       '../core/core.gyp:webcore',
     ],
     'defines': [
       'WEBKIT_IMPLEMENTATION=1',

[abarth-chromium, 2013/06/17 20:30:04]

I thought WEBKIT_IMPLEMENTATION controlled whether we import or export
symbols...

       'INSIDE_WEBKIT',
     ],
     'sources': [
       '<@(modules_files)',
     ],
+    'conditions': [
+      ['component=="shared_library"', {
+          'defines': [
+              'WEBKIT_DLL',

[abarth-chromium, 2013/06/17 17:33:02]

This sort of thing should be in config.gyp.

+          ],
+      }],
+    ],
     # Disable c4267 warnings until we fix size_t to int truncations.
     'msvs_disabled_warnings': [ 4267, 4334, ]
   }],
 }