toolbarGroups - impossible to remove subgroup that has the same name as group

[Wiktor Walc]

Default configuration:

CKEDITOR.replace( 'editor1', {
	toolbarGroups : [
		{ name: 'document',    groups: [ 'mode', 'document', 'doctools' ] },
		{ name: 'clipboard',   groups: [ 'clipboard', 'undo' ] }, // <----
		{ name: 'editing',     groups: [ 'find', 'selection', 'spellchecker' ] },
		{ name: 'forms' },
		'/',
		{ name: 'basicstyles', groups: [ 'basicstyles', 'cleanup' ] },
		{ name: 'paragraph',   groups: [ 'list', 'indent', 'blocks', 'align', 'bidi' ] },
		{ name: 'links' },
		{ name: 'insert' },
		'/',
		{ name: 'styles' },
		{ name: 'colors' },
		{ name: 'tools' },
		{ name: 'others' },
		{ name: 'about' }
	]
} );

Undo subgroup removed (undo/redo buttons are gone):

CKEDITOR.replace( 'editor1', {
	toolbarGroups : [
		{ name: 'document',    groups: [ 'mode', 'document', 'doctools' ] },
		{ name: 'clipboard',   groups: [ 'clipboard' ] }, // <----
		{ name: 'editing',     groups: [ 'find', 'selection', 'spellchecker' ] },
		{ name: 'forms' },
		'/',
		{ name: 'basicstyles', groups: [ 'basicstyles', 'cleanup' ] },
		{ name: 'paragraph',   groups: [ 'list', 'indent', 'blocks', 'align', 'bidi' ] },
		{ name: 'links' },
		{ name: 'insert' },
		'/',
		{ name: 'styles' },
		{ name: 'colors' },
		{ name: 'tools' },
		{ name: 'others' },
		{ name: 'about' }
	]
} );

Clipboard subgroup removed (clipboard buttons are still available):

CKEDITOR.replace( 'editor1', {
	toolbarGroups : [
		{ name: 'document',    groups: [ 'mode', 'document', 'doctools' ] },
		{ name: 'clipboard',   groups: [ 'undo' ] }, // <----
		{ name: 'editing',     groups: [ 'find', 'selection', 'spellchecker' ] },
		{ name: 'forms' },
		'/',
		{ name: 'basicstyles', groups: [ 'basicstyles', 'cleanup' ] },
		{ name: 'paragraph',   groups: [ 'list', 'indent', 'blocks', 'align', 'bidi' ] },
		{ name: 'links' },
		{ name: 'insert' },
		'/',
		{ name: 'styles' },
		{ name: 'colors' },
		{ name: 'tools' },
		{ name: 'others' },
		{ name: 'about' }
	]
} );