Automatically generate constructor attributes on WorkerContext

Source/bindings/derived_sources.gyp

Index: Source/bindings/derived_sources.gyp
diff --git a/Source/bindings/derived_sources.gyp b/Source/bindings/derived_sources.gyp
index 6f56264be3606211f2d2d402b5cf92833ca43fb0..8b3f4b120b3c33dd4f90bfc3f18499950d4a890e 100644
--- a/Source/bindings/derived_sources.gyp
+++ b/Source/bindings/derived_sources.gyp
@@ -111,6 +111,7 @@
        'outputs': [
          '<(SHARED_INTERMEDIATE_DIR)/supplemental_dependency.tmp',
          '<(SHARED_INTERMEDIATE_DIR)/DOMWindowConstructors.idl',
+         '<(SHARED_INTERMEDIATE_DIR)/WorkerContextConstructors.idl',
        ],
        'msvs_cygwin_shell': 0,
        'action': [
@@ -122,6 +123,8 @@
          '<(SHARED_INTERMEDIATE_DIR)/supplemental_dependency.tmp',
          '--window-constructors-file',
          '<(SHARED_INTERMEDIATE_DIR)/DOMWindowConstructors.idl',
+         '--workercontext-constructors-file',
+         '<(SHARED_INTERMEDIATE_DIR)/WorkerContextConstructors.idl',
          '<@(write_file_only_if_changed)',
        ],
        'message': 'Resolving partial interfaces dependencies in all IDL files',
@@ -168,6 +171,7 @@
           '../core/scripts/preprocessor.pm',
           '<!@pymod_do_main(supplemental_idl_files <@(idl_files))',
           '<(SHARED_INTERMEDIATE_DIR)/DOMWindowConstructors.idl',
+          '<(SHARED_INTERMEDIATE_DIR)/WorkerContextConstructors.idl',
         ],
         'outputs': [
           # FIXME:  The .cpp file should be in webkit/bindings once