Add ShadowRootInit dictionary.

Source/core/core.gypi

 {
     'includes': [
         'core_generated.gypi',
     ],
     'variables': {
         # Files for which bindings (.cpp and .h files) will be generated
         'core_idl_files': [
             'animation/KeyframeEffect.idl',
             'animation/EffectModel.idl',
             'animation/AnimationEffectReadOnly.idl',
@@ skipping 3552 matching lines @@
         ],
         'core_dictionary_idl_files': [
             'animation/KeyframeEffectOptions.idl',
             'animation/ComputedTimingProperties.idl',
             'css/FontFaceDescriptors.idl',
             'css/FontFaceSetLoadEventInit.idl',
             'css/MediaQueryListEventInit.idl',
             'dom/DOMPointInit.idl',
             'dom/ElementRegistrationOptions.idl',
             'dom/MutationObserverInit.idl',
+            'dom/shadow/ShadowRootInit.idl',
             'events/AnimationEventInit.idl',
             'events/AnimationPlayerEventInit.idl',
             'events/ApplicationCacheErrorEventInit.idl',
             'events/AutocompleteErrorEventInit.idl',
             'events/CompositionEventInit.idl',
             'events/CustomEventInit.idl',
             'events/ErrorEventInit.idl',
             'events/EventInit.idl',
             'events/FocusEventInit.idl',
             'events/HashChangeEventInit.idl',
@@ skipping 35 matching lines @@
             '<(blink_core_output_dir)/css/FontFaceSetLoadEventInit.cpp',
             '<(blink_core_output_dir)/css/FontFaceSetLoadEventInit.h',
             '<(blink_core_output_dir)/css/MediaQueryListEventInit.cpp',
             '<(blink_core_output_dir)/css/MediaQueryListEventInit.h',
             '<(blink_core_output_dir)/dom/DOMPointInit.cpp',
             '<(blink_core_output_dir)/dom/DOMPointInit.h',
             '<(blink_core_output_dir)/dom/ElementRegistrationOptions.cpp',
             '<(blink_core_output_dir)/dom/ElementRegistrationOptions.h',
             '<(blink_core_output_dir)/dom/MutationObserverInit.cpp',
             '<(blink_core_output_dir)/dom/MutationObserverInit.h',
+            '<(blink_core_output_dir)/dom/shadow/ShadowRootInit.cpp',
+            '<(blink_core_output_dir)/dom/shadow/ShadowRootInit.h',
             '<(blink_core_output_dir)/events/AnimationEventInit.cpp',
             '<(blink_core_output_dir)/events/AnimationEventInit.h',
             '<(blink_core_output_dir)/events/AnimationPlayerEventInit.cpp',
             '<(blink_core_output_dir)/events/AnimationPlayerEventInit.h',
             '<(blink_core_output_dir)/events/ApplicationCacheErrorEventInit.cpp',
             '<(blink_core_output_dir)/events/ApplicationCacheErrorEventInit.h',
             '<(blink_core_output_dir)/events/AutocompleteErrorEventInit.cpp',
             '<(blink_core_output_dir)/events/AutocompleteErrorEventInit.h',
             '<(blink_core_output_dir)/events/CompositionEventInit.cpp',
             '<(blink_core_output_dir)/events/CompositionEventInit.h',
@@ skipping 282 matching lines @@
             'style/ComputedStyleTest.cpp',
             'style/OutlineValueTest.cpp',
             'style/SVGComputedStyleTest.cpp',
             'testing/PrivateScriptTestTest.cpp',
             'timing/MemoryInfoTest.cpp',
             'workers/WorkerThreadTest.cpp',
             'xml/parser/SharedBufferReaderTest.cpp',
         ],
     }
 }