src/vs/editor/browser/widget/codeEditorWidget.ts/CodeEditorWidget/removeDecorationsByType
class CodeEditorWidget:	public removeDecorationsByType(decorationTypeKey: string): void {
		// remove decorations for type and sub type
		const oldDecorationsIds = this._decorationTypeKeysToIds[decorationTypeKey];
		if (oldDecorationsIds) {
			this.deltaDecorations(oldDecorationsIds, []);
		}
		if (this._decorationTypeKeysToIds.hasOwnProperty(decorationTypeKey)) {
			delete this._decorationTypeKeysToIds[decorationTypeKey];
		}
		if (this._decorationTypeSubtypes.hasOwnProperty(decorationTypeKey)) {
			delete this._decorationTypeSubtypes[decorationTypeKey];
		}
	}