Introduce WebFrameWidget to Blink

Source/web/web.gypi

 {
   'variables': {
     'web_files': [
       'AssertMatchingEnums.cpp',
       'AssociatedURLLoader.cpp',
       'AssociatedURLLoader.h',
       'ChromeClientImpl.cpp',
       'ChromeClientImpl.h',
       'ColorChooserPopupUIController.cpp',
       'ColorChooserPopupUIController.h',
@@ skipping 134 matching lines @@
       'WebEntities.cpp',
       'WebEntities.h',
       'WebFileChooserCompletionImpl.cpp',
       'WebFileChooserCompletionImpl.h',
       'WebFontDescription.cpp',
       'WebFontImpl.cpp',
       'WebFontImpl.h',
       'WebFormControlElement.cpp',
       'WebFormElement.cpp',
       'WebFrame.cpp',
+      'WebFrameWidgetImpl.cpp',
+      'WebFrameWidgetImpl.h',
       'WebGeolocationController.cpp',
       'WebGeolocationError.cpp',
       'WebGeolocationPermissionRequest.cpp',
       'WebGeolocationPermissionRequestManager.cpp',
       'WebGeolocationPosition.cpp',
       'WebGlyphCache.cpp',
       'WebHeap.cpp',
       'WebHelperPluginImpl.cpp',
       'WebHelperPluginImpl.h',
       'WebHistoryItem.cpp',
@@ skipping 178 matching lines @@
       ['os_posix==1 and OS!="mac"',
         {
           'web_unittest_files': [
             'tests/LocaleICUTest.cpp',
           ],
         }
       ],
     ],
   },
 }