bug#10957: 24.0.94; doc-string of x-get-selection-internal makes no sense

[Leo]

,----[ C-h f x-get-selection-internal RET ]
| x-get-selection-internal is a built-in function in `C source code'.
| 
| (x-get-selection-internal ARG1 ARG2 &optional ARG3 ARG4)
| 
| Return text selected from some X window.
| SELECTION-SYMBOL is typically `PRIMARY', `SECONDARY', or `CLIPBOARD'.
| (Those are literal upper-case symbol names, since that's what X expects.)
| TARGET-TYPE is the type of data desired, typically `STRING'.
| 
| TIME-STAMP is the time to use in the XConvertSelection call for foreign
| selections.  If omitted, defaults to the time for the last event.
| 
| TERMINAL should be a terminal object or a frame specifying the X
| server to query.  If omitted or nil, that stands for the selected
| frame's display, or the first available X display.
| 
| On Nextstep, TIME-STAMP and TERMINAL are unused.
| 
| [back]
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