showCaret();
showCaret(caretLine);
void doSelectionLineDown() {	int oldCaretX = caretX;		if (isSingleLine()) {		return;	}	if (caretLine == content.getLineCount() - 1) {		caretOffset = content.getCharCount();	}	else {		doLineDown();	}	setMouseWordSelectionAnchor();		// select first and then scroll to reduce flash when key 	// repeat scrolls lots of lines	doSelection(SWT.RIGHT);	showCaret();	// save the original horizontal caret position	caretX = oldCaretX;}