Gets a command to apply (or cancel) border settings of the left border for the selected cells.
readonly toggleTableCellLeftBorder: ToggleTableCellLeftBorderCommand
A ToggleTableCellLeftBorderCommand object that provides methods for executing the command and checking its state.
You can invoke this command by calling the execute method.
The execute method checks the command state (obtained using the getState method) before executing, and decides whether the action can be performed. The execute and getState methods are members of the ToggleTableCellLeftBorderCommand class.
The command applies border settings that you can modify using the RichEditCommands.changeTableBorderRepositoryItem command.