VS: Remove unused method from VS 9 generator

Source/cmGlobalVisualStudio9Generator.cxx

@@ -121,14 +121,6 @@ cmLocalGenerator *cmGlobalVisualStudio9Generator::CreateLocalGenerator()
   return lg;
 }
 
-//----------------------------------------------------------------------------
-void cmGlobalVisualStudio9Generator
-::EnableLanguage(std::vector<std::string>const &  lang,
-                 cmMakefile *mf, bool optional)
-{
-  cmGlobalVisualStudio8Generator::EnableLanguage(lang, mf, optional);
-}
-
 //----------------------------------------------------------------------------
 std::string cmGlobalVisualStudio9Generator::GetUserMacrosDirectory()
 {

Source/cmGlobalVisualStudio9Generator.h

@@ -35,8 +35,6 @@ public:
    * Try to determine system infomation such as shared library
    * extension, pthreads, byte order etc.
    */
-  virtual void EnableLanguage(std::vector<std::string>const& languages,
-                              cmMakefile *, bool optional);
   virtual void WriteSLNHeader(std::ostream& fout);
 
   /**