This patch adds possibility of searching a public symbol with name and type in a symbol file, not only in a symtab. It is helpful when working with PE, because PE's symtabs contain only imported / exported symbols only. Such a search is required for e.g. evaluation of an expression that calls some function of the debuggee.
A few weeks ago on lldb-dev there was a discussion of this, it is called Symtab for PECOFF.