LaTeX export: Allow parenthesis before exponent of subscript

Keith writes:

> I noticed something strange and I think it's might be a bug converting
> to tex file. I've been trying to put a special symbol inside a
> bracket, e.g.
>
>  air temperature (degree Celsius)
>
> and the symbol should look like ^{\circ}C in org file. It works well
> if it is standalone. However, when I put the brackets out of it, say
> (^{\circ}C), the pdf output looks bizarre. I have checked the tex
> output and the converting results from orgmode file are
>
>  ^{\circ}C   -->   $^{\circ}$C
>  (^{\circ}C) -->   (^\{\circ}C)

lisp/ChangeLog

@@ -1,3 +1,8 @@
+2010-03-24  Carsten Dominik  <carsten.dominik@gmail.com>
+
+	* org-latex.el (org-export-latex-special-chars): Allow a
+	parenthesis before an exponent or subscript.
+
 2010-03-23  Dan Davison  <davison@stats.ox.ac.uk>
 
 	* org-src.el (org-edit-src-exit): When returning from code edit

lisp/org-latex.el

@@ -1431,7 +1431,7 @@ See the `org-export-latex.el' code for a complete conversion table."
 		       (backward-char 1)))))))
 	'(;"^\\([^\n$]*?\\|^\\)\\(\\\\?\\$\\)\\([^\n$]*\\)$"
 	  "\\(\\(\\\\?\\$\\)\\)"
-	  "\\([a-za-z0-9]+\\|[ \t\n]\\|\\b\\|\\\\\\)\\(_\\|\\^\\)\\({[^{}]+}\\|[a-za-z0-9]+\\|[ \t\n]\\|[:punct:]\\|)\\|{[a-za-z0-9]+}\\|([a-za-z0-9]+)\\)"
+	  "\\([a-za-z0-9()]+\\|[ \t\n]\\|\\b\\|\\\\\\)\\(_\\|\\^\\)\\({[^{}]+}\\|[a-za-z0-9]+\\|[ \t\n]\\|[:punct:]\\|)\\|{[a-za-z0-9]+}\\|([a-za-z0-9]+)\\)"
 	  "\\(.\\|^\\)\\(\\\\\\)\\([ \t\n]\\|[a-zA-Z&#%{}\"]+\\)"
 	  "\\(.\\|^\\)\\(&\\)"
 	  "\\(.\\|^\\)\\(#\\)"