Rewrite relative includes in public/web/

public/blink.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 42 matching lines @@
             # of Blink's API types from places that can't link against Blink. crbug.com/248653
             'target_name': 'blink_minimal',
             'type': 'none',
             'dependencies': [
                 '../Source/platform/blink_platform.gyp:blink_common',
             ],
             'export_dependent_settings': [
                 '../Source/platform/blink_platform.gyp:blink_common',
             ],
         },
+        {
+            # This target adds the include paths required to include from public/,
+            # for code that does not link with Blink.
+            'target_name': 'blink_public',
+            'type': 'none',
+            'include_dirs': [
+                '..'
+            ]
+        }
     ],
 }