Editing WoW:API GetMouseButtonClicked

{{wowapi}}
Returns the name of the button responsible causing the OnClick handler to fire.
 buttonName = GetMouseButtonClicked();

== Returns ==
; buttonName : String - name of the button responsible for the innermost OnClick event. For example, "LeftButton"

== Details ==
* The buttonName return value may be an arbitrary string (as the {{api|Button Click|Button:Click}} method accepts arbitrary arguments).
* If there are multiple OnClick handler dispatches on the call stack, information about the innermost one is returned.