Support partial interface for test support idls

Source/core/core.gypi

 {
     'variables': {
         'core_idl_files': [
             'css/CSS.idl',
             'css/CSSCharsetRule.idl',
             'css/CSSFontFaceLoadEvent.idl',
             'css/CSSFontFaceRule.idl',
             'css/CSSHostRule.idl',
             'css/CSSImportRule.idl',
             'css/CSSKeyframeRule.idl',
@@ skipping 3489 matching lines @@
         ],
         'webcore_test_support_idl_files': [
           'testing/GCObservation.idl',
           'testing/Internals.idl',
           'testing/InternalProfilers.idl',
           'testing/InternalSettings.idl',
           'testing/LayerRect.idl',
           'testing/LayerRectList.idl',
           'testing/MallocStatistics.idl',
           'testing/TypeConversions.idl',
+        ],
+        'generated_webcore_test_support_idl_files': [
           '<(SHARED_INTERMEDIATE_DIR)/blink/InternalSettingsGenerated.idl',
           '<(SHARED_INTERMEDIATE_DIR)/blink/InternalRuntimeFlags.idl',
         ],
         'webcore_test_support_files': [
             'testing/v8/WebCoreTestSupport.cpp',
             'testing/v8/WebCoreTestSupport.h',
             'testing/GCObservation.cpp',
             'testing/GCObservation.h',
             'testing/InspectorFrontendClientLocal.cpp',
             'testing/InspectorFrontendClientLocal.h',
@@ skipping 136 matching lines @@
                 'bison_exe': 'bison',
                 # We specify a preprocess so it happens locally and won't get
                 # distributed to goma.
                 # FIXME: /usr/bin/gcc won't exist on OSX forever. We want to
                 # use /usr/bin/clang once we require Xcode 4.x.
                 'preprocessor': '--preprocessor "/usr/bin/gcc -E -P -x c++"'
               }],
          ],
     }
 }