bug#12140: 24.1; mouse-drag-track: Args out of range: 2746, 71308

[Chong Yidong]

Leo <sdl.web@gmail.com> writes:

> 1. Emacs -q
> 2. C-h i m elisp RET
> 3. Use mouse-1 to click the buffer
> 3. 1 ; enter the first node
> 4. Use mouse-1 to click the buffer
>
> Debugger entered--Lisp error: (args-out-of-range 1 71543)
>   buffer-substring-no-properties(1 71543)
>   mouse-drag-track((down-mouse-1 (#<window 3 on *info*> 71580 (291
> . 474) 214100214 nil 71580 (36 . 31) nil (3 . 14) (8 . 15))) t)
>   mouse-drag-region((down-mouse-1 (#<window 3 on *info*> 71580 (291
> . 474) 214100214 nil 71580 (36 . 31) nil (3 . 14) (8 . 15))))
>   call-interactively(mouse-drag-region nil nil)

I'm pretty sure this is already fixed in the trunk, and in the emacs-24
branch.  Please check.