[import] Cleanup: get rid of ad-hoc state machine.

Source/core/core.gypi

 {
     'variables': {
         # Files for which bindings (.cpp and .h files) will be generated
         'core_idl_files': [
             'animation/Animation.idl',
             'animation/Player.idl',
             'animation/TimedItem.idl',
             'css/CSS.idl',
             'css/CSSCharsetRule.idl',
             'css/CSSFontFaceLoadEvent.idl',
@@ skipping 2268 matching lines @@
             'html/HTMLImportsController.cpp',
             'html/HTMLImportsController.h',
             'html/HTMLImportChild.cpp',
             'html/HTMLImportChild.h',
             'html/HTMLImportChildClient.h',
             'html/HTMLImportLoader.cpp',
             'html/HTMLImportLoader.h',
             'html/HTMLImportLoaderClient.h',
             'html/HTMLImportResourceOwner.cpp',
             'html/HTMLImportResourceOwner.h',
+            'html/HTMLImportStateResolver.cpp',
+            'html/HTMLImportStateResolver.h',
             'html/HTMLInputElement.cpp',
             'html/HTMLKeygenElement.cpp',
             'html/HTMLKeygenElement.h',
             'html/HTMLLIElement.cpp',
             'html/HTMLLIElement.h',
             'html/HTMLLabelElement.cpp',
             'html/HTMLLabelElement.h',
             'html/HTMLLegendElement.cpp',
             'html/HTMLLegendElement.h',
             'html/HTMLLinkElement.cpp',
@@ skipping 972 matching lines @@
             'html/track/vtt/BufferedLineReaderTest.cpp',
             'html/track/vtt/VTTScannerTest.cpp',
             'frame/ImageBitmapTest.cpp',
             'rendering/RenderOverflowTest.cpp',
             'rendering/shapes/BoxShapeTest.cpp',
             'testing/UnitTestHelpers.h',
             'testing/UnitTestHelpers.cpp',
         ],
     }
 }